doc(README): precise how to launch local testnet

README.md

@@ -71,6 +71,42 @@ CAUTION: In order for **Polkadot-JS Apps** to be able to fully understand the in
 If you want to see the multi-node consensus algorithm in action, refer to
 [our Start a Private Network tutorial](https://substrate.dev/docs/en/tutorials/start-a-private-network/).
 
+### Purge previous lacal testnet
+
+```
+./target/release/lc-core purge-chain --base-path /tmp/alice --chain local
+./target/release/lc-core purge-chain --base-path /tmp/bob --chain local
+
+```
+
+### Start Alice's node
+
+```bash
+./target/release/lc-core \
+  --base-path /tmp/alice \
+  --chain local \
+  --alice \
+  --port 30333 \
+  --ws-port 9945 \
+  --rpc-port 9933 \
+  --node-key 0000000000000000000000000000000000000000000000000000000000000001 \
+  --validator
+```
+
+### Start Bob's node
+
+```bash
+./target/release/lc-core \
+  --base-path /tmp/bob \
+  --chain local \
+  --bob \
+  --port 30334 \
+  --ws-port 9946 \
+  --rpc-port 9934 \
+  --validator \
+  --bootnodes /ip4/127.0.0.1/tcp/30333/p2p/12D3KooWEyoppNCUx8Yx66oV9fJnriXwCcXwDDUA2kj6vnc6iDEp
+```
+
 ## Project Structure
 
 A Substrate project such as this consists of a number of components that are spread across a few
@@ -96,7 +132,7 @@ There are several files in the `node` directory - take special note of the follo
   [chain specification](https://substrate.dev/docs/en/knowledgebase/integrate/chain-spec) is a
   source code file that defines a Substrate chain's initial (genesis) state. Chain specifications
   are useful for development and testing, and critical when architecting the launch of a
-    production chain. Take note of the `development_config` and `testnet_genesis` functions, which
+  production chain. Take note of the `development_chain_spec` and `testnet_genesis` functions, which
   are used to define the genesis state for the local development chain configuration. These
   functions identify some
   [well-known accounts](https://substrate.dev/docs/en/knowledgebase/integrate/subkey#well-known-keys)