Suggestions:that take some emotional energy and restraint, but don't require much time or any money (and might actually save you time):

• Be kind to yourself and others.
• Don't self-criticize because you aren't moving "fast enough" in the direction you think is best; it's okay to be proud of progress, even minor progress.
• Don't criticize others unless you really believe it will be helpful (imagine how helpful the average piece of online criticism is, and remember that you might be closer to "average" than you think, especially if your response is fueled by anger and you don't care very much about the other person's welfare).
• Try to think about measures of effectiveness, especially scale, in your daily life. Getting used to "seeing through an EA lens" can help to guide you toward other ways of helping the world.
• This may be most applicable when it comes to news and social media. If you see a huge argument erupt over a small incident, consider whether your efforts will be helpful before you jump in to contribute. And consider, before reading the whole thread, whether there are other things you could be reading that concern a larger number of people, with more at stake.
• This doesn't mean completely abandoning local issues or your social circle, of course -- but it does mean remembering that what news outlets prioritize is not inherently important just because it is "news".
• Clean up your systems.
• No matter what you want to work on the future, no matter how long it will take, you'll want to have certain resources available when you arrive. These include things like "a coherent to-do list", "a reasonably well-organized physical space", "a nutritious diet", and "slack".
• If you plan to help the world once your life is "in order" (something I've heard many times), putting your life in order is helping the world.
• I won't turn this answer into a post about personal productivity. Things that have been helpful to many people I know include Getting Things Done and The Life-Changing Magic of Tidying Up, but reading some personal productivity websites and doing simple, commonsense things will help a lot for people who aren't yet doing said things.

See also here for more suggestions: https://www.effectivealtruism.org/get-involved/

I don't think that anyone knows a clear right answer to your question (at least, I don't). What is 'easiest', I guess, depends on your personal situation. If you have enough money, donating is probably the easiest start. If you are early in your career, maybe read up on 80.000 hours.

I have a simple list of powerful actions you can take right now. Because I'm in the same boat, even though I study psychology in uni, I have been thinking of how to do more good every day. I think the EA Forum can get a bit theoretical and I hope to change that because, indeed, we need practical activities to do in order to effectively be altruistic.

1. What does a charity/person need? Can you give it to them?

It seems like another lame piece of advice, but if you ask what the biggest challenges a charity/person faces, you can attempt to do some legwork for them. I learned how charities wanted help with getting their fundraising known and so every day I sent a single email to a different editor to let them know about the fundraiser campaign the charity was holding. 1:10 got back to me, but within the month that meant the charity had three new media articles written about them which they wouldn't have without my simple outreach.

2. They all want money. How can you give it to them?

This one makes charities really thankful! First, make sure the charity IS effective and that you DO like them. You can raise money for a charity via your own job, a small fundraising campaign (look up 'fundraising ideas') or something outside the box (I participated in a low-risk, paid clinical research trial to get money for a charity).

3. Small acts

There's heaps. Recently, with covid, I have been thanking any essential workers I pass, "Thank you for being an essential worker." I have also tried complimenting all of my friends, family and strangers with something positive about them.

4. Dominant action

This is a type of action in business which secures a market, as if you hold a monopoly over it, think of it like cornering a chess piece. In person, it simply looks like sharing time with a powerful connection. If you have any career dreams or even passing interests in a hobby, reach out to pioneers of that field and let them know that they inspire you. If they reply, you can get to know them, as if you can have a short call/interview and then as they begin to like you, let them know about a charity you love. If they seem happy about it, ask if they might donate to complete a specific project (make sure you've done your research) of the charity's or, if the person doesn't seem interested, you can organise a few weeks later to do a fundraising idea and then ask for them to donate anything they can afford! It works!