The Levels of Donation post contains lots of good advice on the same.
I aim to continue giving to the Fish Welfare Initiative (FWI)! Occasionally, I might give to the Shrimp Welfare project or the Animal Welfare Fund. My reasoning for doing so is as follows:
I took the Try Giving Pledge a few months ago and plan to give somewhere between 2%-5% of my income this year! If you are a graduate candidate, an early career professional, or just generally new to giving, I recommend taking the pledge. I have been able to spend money on essentials, extras, and savings and still comfortably give $ to my favorite charities.
I randomly checked FWI's website before posting this, and it turns out they have a funding gap of $800K — consider giving here!