Update contributing guide

README.md

@@ -27,8 +27,8 @@ Creates a new web3 instance with http provider.
 
 ```golang
 // change to your rpc provider
-var infuraURL = "https://mainnet.infura.io/v3/<API-Key>"
-web3, err := web3.NewWeb3(infuraURL)
+var rpcProviderURL = "https://rpc.flashbots.net"
+web3, err := web3.NewWeb3(rpcProviderURL)
 if err != nil {
     panic(err)
 }
@@ -93,9 +93,24 @@ fmt.Println("Latest nonce: ", nonce)
 Init contract api
 
 ```golang
-abiString := "" // abi string
-contractAddr := "" // contract address
-contract, err := web3.Eth.NewContract(abiString, contractAddr )
+abiString := `[
+	{
+		"constant": true,
+		"inputs": [],
+		"name": "totalSupply",
+		"outputs": [
+			{
+				"name": "",
+				"type": "uint256"
+			}
+		],
+		"payable": false,
+		"stateMutability": "view",
+		"type": "function"
+	}
+]`
+contractAddr := "0x6B175474E89094C44Da98b954EedeAC495271d0F" // contract address
+contract, err := web3.Eth.NewContract(abiString, contractAddr)
 if err != nil {
     panic(err)
 }
@@ -158,6 +173,38 @@ fmt.Printf("Send approve tx hash %v\n", txHash)
 - **[Contract API](./examples/contract/erc20.go)**
 - **[EIP1559 API](./examples/eip1559/main.go)**
 
+## Contributing
+
+Go-Web3 welcome contributions. Please follow the guidelines when opening issues and contributing code to the repo.
+
+### Contributing
+
+We follow the [fork-and-pull](https://help.github.com/en/articles/about-collaborative-development-models) Git workflow:
+
+ 1. **Fork** the repo on GitHub
+ 2. **Clone** it to your own machine
+ 3. **Commit** changes to your fork
+ 4. **Push** changes to your fork
+ 5. Submit a **Pull request** for review
+
+**NOTE:** Be sure to merge the latest changes before making a pull request!
+
+### Pull Requests
+
+As outlined in Keavy McMinn's article ["How to write the perfect pull request"](https://github.blog/2015-01-21-how-to-write-the-perfect-pull-request/), you should include:
+
+  1. The purpose of the PR
+  2. A brief overview of what you did
+  3. Tag any issues that the PR relates to and [close issues with a keyword](https://help.github.com/en/articles/closing-issues-using-keywords)
+  4. What kind of feedback you're looking for (if any)
+  5. Tag individuals you want feedback from (if any)
+
+### Issues
+
+Feel free to submit issues and enhancement requests [here](https://github.com/chenzhijie/go-web3/issues/new). Please consider [how to ask a good question](https://stackoverflow.com/help/how-to-ask) and take the time to research your issue before asking for help.
+
+Duplicate questions will be closed.
+
 ## License
 
 The go-web3 source code is available under the [LGPL-3.0](LICENSE) license.