Restoring razors is fun but requires a lot of spare time. A magnetic sanding block is useful and you need a range of sanding paper of e.g. 80, 120, 180, 240, 400, 600, 800, 1000, 1500 and 2000 depending on the state of your razor and how shiny you want it to get.

Creating custom scales is more complicated but also more rewarding imo.