Detailed Instructions

First, you must select a test network that matches the mainnet you intend to use. For Ethereum development, popular choices are Sepolia or Goerli. For other chains like Polygon, use the Mumbai testnet. You will then configure your Web3 wallet (like MetaMask) to connect to this network.

• Sub-step 1: Add the Testnet Network. In MetaMask, click the network dropdown and select "Add network." Manually enter the RPC details. For Sepolia, use:
  • Network Name: Sepolia Test Network
  • RPC URL: https://sepolia.infura.io/v3/YOUR_INFURA_KEY
  • Chain ID: 11155111
  • Currency Symbol: SepoliaETH
• Sub-step 2: Acquire Test Tokens. Visit a faucet for your chosen network. For Sepolia, go to https://sepoliafaucet.com. You will need to connect your wallet and request test ETH, which is required for paying gas fees on the testnet.
• Sub-step 3: Verify Connection and Balance. In your wallet, ensure the network is switched to the testnet. Check your balance to confirm you received the faucet funds.

Tip: Always double-check RPC URLs from official sources to avoid phishing. Keep your Infura Project ID private.

Detailed Instructions

Navigate to a Decentralized Exchange (DEX) that has a frontend deployed on the testnet. A common choice is a testnet version of Uniswap (v3) on Sepolia at https://uniswap-v3.sepolia.xdeploy.app/. This allows you to practice swaps, adds liquidity, and interacts with liquidity pools without financial risk.

• Sub-step 1: Connect Your Wallet. On the DEX website, click "Connect Wallet" and authorize the connection with your testnet-configured MetaMask.
• Sub-step 2: Perform a Token Swap. Select two tokens. You can use the official test tokens, like Wrapped SepoliaETH (WETH) or other ERC-20 faucet tokens. Enter an amount and execute the swap. Your wallet will prompt you to confirm the transaction and pay a small amount of test ETH for gas.
• Sub-step 3: Analyze the Transaction. After confirmation, view the transaction on a block explorer like https://sepolia.etherscan.io. Look for details like gas used, status, and token balances to understand on-chain activity.

Tip: Use this step to experiment with slippage tolerance and transaction deadlines to see how they affect your swaps.

Detailed Instructions

Lending protocols are a core DeFi primitive. Visit the testnet interface for Aave at https://testnet.aave.com/. Ensure your wallet is connected to the Polygon Mumbai network, as that's where the test app is deployed. Here, you can simulate supplying assets to earn interest and borrowing against your collateral.

• Sub-step 1: Supply Test Assets. Navigate to the "Dashboard" and click "Supply" on an asset like Test DAI or Test USDC. Approve the token contract first, then deposit an amount. You will receive aTokens (e.g., aPolTestDAI) representing your supplied balance and accruing interest.
• Sub-step 2: Borrow Against Collateral. Once you have supplied assets, they act as collateral. Go to the "Borrow" section, select an asset, and specify an amount. The protocol will show your Health Factor, a critical metric indicating the safety of your loan. Execute the borrow transaction.
• Sub-step 3: Monitor Positions. Use the dashboard to track your supplied balance, borrowed amount, and health factor. Try repaying a portion of the loan to see how it affects your position.

Tip: Intentionally let your health factor drop near the liquidation threshold to understand the risks and mechanics of liquidation events in a safe environment.

Detailed Instructions

For advanced practice, deploy your own contract. Use the browser-based Remix IDE at https://remix.ethereum.org. This step teaches you about gas estimation, contract verification, and interaction.

• Sub-step 1: Write a Simple Contract. Create a new file (SimpleStorage.sol). Write a basic contract that stores and retrieves a number.

solidityCopy
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;
contract SimpleStorage {
    uint256 private storedData;
    function set(uint256 x) public {
        storedData = x;
    }
    function get() public view returns (uint256) {
        return storedData;
    }
}

• Sub-step 2: Compile and Deploy. In the "Solidity Compiler" tab, compile the contract. Switch to the "Deploy & Run Transactions" tab. Set the "Environment" to "Injected Provider - MetaMask" and ensure your wallet is on Sepolia. Click "Deploy" and confirm the transaction in MetaMask.
• Sub-step 3: Interact with Your Contract. Once deployed, the contract appears in Remix. Use the provided buttons to call the set and get functions, sending transactions for set and making calls for get. Copy the contract address and look it up on Sepolia Etherscan.

Tip: This process incurs gas fees paid in test ETH. Always check the estimated gas in your wallet before confirming a deployment transaction.

Detailed Instructions

First, you must configure a Web3 wallet like MetaMask to connect to a test network. For Ethereum, popular choices are the Sepolia or Goerli testnets. In MetaMask, add the network by entering the RPC URL, chain ID, and currency symbol. Next, you need to acquire testnet ETH or other tokens to simulate transactions. Use a faucet to request free tokens; for Sepolia, you can visit sepoliafaucet.com and enter your wallet address. This provides the gas fees needed for transactions.

• Sub-step 1: In MetaMask, click the network dropdown and select "Add network".
• Sub-step 2: Enter the Sepolia details: RPC URL https://rpc.sepolia.org, Chain ID 1115511, Symbol SepoliaETH.
• Sub-step 3: Visit a faucet, paste your 0x... wallet address, and request tokens. Wait for confirmation.

Tip: Always double-check RPC URLs from official sources to avoid phishing. Keep your private keys secure, even on testnets.

Detailed Instructions

Navigate to a Decentralized Exchange (DEX) that supports your chosen testnet, such as Uniswap on Sepolia. Connect your wallet to the DEX interface. You'll simulate swapping one test token for another. First, ensure you have a balance of the input token. You may need to acquire test versions of tokens like DAI or USDC from a separate faucet. The swap process involves approving the DEX contract to spend your tokens, then executing the trade. Monitor the slippage tolerance and gas fees to understand transaction costs.

• Sub-step 1: Go to app.uniswap.org, click "Connect Wallet", and select MetaMask.
• Sub-step 2: Select SepoliaETH as the input and a test token like 0x... (mock DAI) as the output.
• Sub-step 3: Click "Swap", review the quote, and confirm the transaction in MetaMask. Check the transaction hash on a block explorer like sepolia.etherscan.io.

Tip: Use small amounts for initial tests. Analyze the transaction details on the explorer to learn about contract interactions and event logs.

Detailed Instructions

Practice supplying liquidity to a lending protocol such as Aave on a testnet. This involves depositing a test asset to earn interest and potentially using it as collateral. Visit the Aave testnet interface (e.g., testnet.aave.com for Sepolia) and connect your wallet. You'll need test tokens like aWETH or aDAI. The process includes approving the protocol contract and then executing the deposit. After supplying, you can view your health factor and borrowing power, which are critical for understanding safe leverage.

• Sub-step 1: Connect your wallet to the Aave testnet app and navigate to the "Dashboard".
• Sub-step 2: Select "Supply" for an asset like SepoliaETH, enter an amount (e.g., 0.1), and click "Approve".
• Sub-step 3: After approval, confirm the supply transaction. Use the following command in a console to check your balance via ethers.js: ```js const balance = await aaveContract.balanceOf(yourAddress);

codeCopy

> **Tip:** Experiment with borrowing against your collateral to see how it affects your health factor, but avoid liquidation thresholds.

Detailed Instructions

Simulate yield farming by first providing liquidity to a liquidity pool on a testnet DEX. This typically involves depositing two tokens in a specific ratio to receive LP (Liquidity Provider) tokens. Then, stake these LP tokens in a farm or gauge to earn additional rewards. Use a platform like a testnet version of Curve or SushiSwap. The steps include approving token spends, adding liquidity, and then approving and staking the LP tokens. Track your APY (Annual Percentage Yield) and impermanent loss risks in a risk-free environment.

• Sub-step 1: On a testnet DEX, navigate to the "Pool" section and add liquidity for a pair like test DAI/test USDC.
• Sub-step 2: After receiving LP tokens, go to the "Farm" section, select your pool, and click "Stake".
• Sub-step 3: Approve the staking contract and confirm the transaction. Monitor rewards accrual with a script: ```bash cast call <farmContract> 'earned(address)' $(cast --to-checksum-address YOUR_ADDRESS) --rpc-url SEPOLIA_RPC

codeCopy

> **Tip:** This process helps you understand complex DeFi composability without financial risk. Always verify contract addresses from official docs.