I had the pleasure of attempting to give feedback at the Bring Your Own Animation booth at the Siggraph TechTalk event in London a while back. I say "attempt" because as it worked out, I gave no animation feedback. I gave feedback to a guy who had made a video that looked like it was made of individual paintings (it was a clever filter with some hand fixing), but that was limited in what I could tell him. It just wasn't animation.
The good thing was that there were people to talk to and in one particular case there was a student, just starting out, who asked me for advice at the start of his animation education. I will now share with you what I told him, as I think it is worth repeating.
1. Don't get ahead of yourself
Learn to walk before you can run. Too often I see students trying to get straight into acting or a big creature shot and making a right mess of it. A bouncing ball is a perfect way to become familiar with the fundamentals of animation. If you can't do a good bouncing ball, you certainly will not be able to do anything more complicated than that. Like any other complex skill, you need to gradually expand to harder and harder tasks. A good series of exercises that go from simple to complex can be found at Animation Island. If you allow yourself to slow down and soak in the lessons learned from doing simpler animations, you'll be better prepared down the line to tackle any situation. Build on the foundations in order to accomplish more complicated tasks.
2. Learn to accept criticism
This is probably the most important animation lesson. As a professional animator, you will get feedback pretty well every day. People that don't respond well to criticism will not last long in this industry. VFX especially wants people that can do the job, not people that argue every point. That being said, you can discuss notes, but I'd recommend getting down the acceptance part first. Other people who have a bit of distance from the material you're working on will have a better vantage point to see what is and isn't working with your shot. And I've always found that feedback from animation supervisors will generally give you a better shot than you could have hoped for. They have loads of experience and a keen eye; don't throw that idly away. As a student, you may or may not have that, but I would recommend being able to take advice from anywhere; your dad saying that something doesn't look right doesn't mean he's stupid and he doesn't know about animation. People naturally analyze movement and know when something is off; it's why the uncanny valley is a thing. A non-animator may not be able to articulate why something is wrong, but don't dismiss when they say something looks weird or unnatural. All critiques, even bad ones, usually have some small gem of value that can be taken away.
3. Don't be afraid to throw work away
Tying into that idea, it's best to walk the tricky line of being passionate about your work, but not being precious. If something isn't working, don't be afraid to cut it out and start again. I used to want to try and keep every single keyframe in a shot that I had done because I had put so much time and effort into it. When I was working on World War Z, I sat next to an animator named Alvise Avati, and I was amazed to see him take something that looked alright to me and throw it away. Start over and have something even better. Trying to shoehorn existing animation into a new idea could be holding your animation back.
4. Develop your eye
Study movement, any movement. People watch. Look at how weight shifts from one leg to another as people walk. Be inspired by what you see. Watch good animation, break it down and watch it frame by frame. Study it. As time goes on, you will start to see what looks natural and what doesn't, what works in your shot and what needs improvement. Sharpen your ability to give feedback, as it is very useful to be able to give yourself feedback and look at things with an objective eye. Giving fellow students feedback (when asked, no one likes unsolicited feedback) can be a good exercise as well as giving feedback on something like the 11 Second Club. I'm not giving you license to be a jerk. Be professional, but be able to also point out what you like about a shot, not just what sticks out as wrong. This will really help your animation, and as you develop your skills and your eye, you'll hopefully be able to spot what isn't working and know what to do about it.
5. Find the workflow that works for you
There's more than one way to skin a cat, as the saying goes, and I think it's hugely important to find your own way to go about it. I think the best thing that you can do for your animation is to have a workflow that you know you can rely on to get good results. Finding this is a matter of trying and failing, seeing what feels comfortable and what doesn't. Different situations also call for different methods. For instance, I usually block stepped, but when I do something that's entirely physical (like a tumbling dinosaur or a falling zombie) I'll do a kind of layered, straight-ahead approach. It's important for you to find these things out for yourself. No one should be dictating how you tackle an animation.
The important thing to realise is that learning is an on-going process. You will always be challenged by new things, but laying down good foundations and having a good grasp of the principles will allow you to meet those challenges with confidence.
Keep on keyframing!