readme update

README.md

-https://block-scout.vercel.app/
+[Design](https://www.figma.com/file/07zoJSAP7Vo655ertmlppA/My_Account?node-id=279%3A1006) | [API Postman](https://www.postman.com/collections/94a0bb509ef7c1bb5250) | [API Swagger](https://app.swaggerhub.com/apis/vbaranov/blockscout-account/2.0.0)
 
-https://www.figma.com/file/07zoJSAP7Vo655ertmlppA/My_Account?node-id=279%3A1006
+-----
+## Local Development
 
-API: https://www.postman.com/collections/94a0bb509ef7c1bb5250
+For local development follow next steps:
+- clone repo
+- install dependencies with `yarn`
+- create local env file `env.local` according to `env.example`
+    - `API_AUTHORIZATION_TOKEN` could be obtain [here](https://blockscout.com/xdai/testnet/auth/auth0_api)
+- run `yarn dev` to spin up local dev server and navigate to the host from logs output