Thanks! Hmmm, I'd say:
- Don't worry about topolgy too much, especially at the beginning.
- Keep it simple starting out, if you want to challenge yourself go for it but within reason, you don't want to discourage yourself (if you want a more indepth explaination I would highly recommend Flow: The Psychology of Optimal Experience - Mihaly Csikszentmihaly)
- Have references https://www.pureref.com/ Incredibly useful tool to have all your references in the same place (it's free!)
- Have fun!
- It's okay to have a break.
The biggest tip that I would have loved to know when i first start out is that the smooth brush can also relax (the video below explains its really well)
Mercurial Forge is an amazing artist, his whole channel has lots of great information.
Because there are so many tutorials out there rather than bombarding you with too much I'll keep it reasonable
I'd say Michael Pavlovich's introduction to zbrush (part 1 is free! as well as a handful of other tutorials) is a solid starting point.
https://cubebrush.co/pavlovich
Also check out Zbrushlive, I found a lot of artists that had a style that I wanted to achieve, then I just grinded through all their videos. I usually have it on in the "background at work" watching at x 1.5 speed.
I think that's enough to get you started. If you ever want more suggestions I'm more than happy to share. I'll start posting useful things I stumble across. I'm curious to see what you sculpt!