1. You need a wallet or node that lets to connect to itself via NWC, like Alby Hub, Coinos, Umbrel and others mentioned.

2. In this wallet/node you generate NWC Connection Secret, that you can scan with app wanting to use it (Alby Go, Primal, Amethyst, Alby Account).

3. You scan or paste the NWC Secret into Alby Go, so you can very quickly and easily use your node/wallet from 1. in your pocket. 

+ It has some additional features like subaccounts, expiry dates, budgets, receive via Lightning Address and can be extended with many - but SEND and RECEIVE are the most essential ;)