To add some extra detail: When you donate ink during Inksgiving, Tapas will return 20% of the ink to you afterwards, so if you donate $10 of ink to people, you'll get $2 worth of ink back in your account after the event.
Honestly I always do absolutely nothing for Inksgiving because it falls right between my favourite big comics event of the year, me and my partner's anniversary and my Birthday, so I instead just donate to people and donate back to creators who donate and I've still generally got a nice chunk of money from it, so my advice from experience is just be a visible and productive person in the community (which you are!).