How can I achieve an androgynous look?

Welcome to EC.
I'm a masculine person so makeup and all that stuff are not really my expertise but I hope I can help you a bit.
First of all, how far are willing to go regarding appearing more feminine? Would you like to pass (be gendered female by strangers) or would you just like to be androgynous?

 

Start small and work your way there. I absolutely guarantee that if you go one day as you are now, then turn up the next day going for 'androgynous' you are going to be noticed and it probably won't end well.

Personally, I would start with your nails. Grow them longer, keep them clean and nicely shaped, maybe clear polish or something so it doesn't really show.

After that, just slowly switch out one item of clothing for something less gendered.

Incidentally, it would be really helpful if you could tell us (or better yet SHOW us) what you look like now so we can target specific things

 

I'm a biological female who is non-binary, not transsexual but more male than female, so my look is everything but feminine although I have rather large breasts and all the bio bits associated with women. Personally, I think that femininity and masculinity have a lot to do with attitude and the way you carry yourself in general. For ex, I lack the testosterone and you can certainly tell that in my facial features and body but I get taken for a boy(not a man but definitely a highschool boy) often when I'm not wearing only a t-shirt. It's not so much my features, a good look will make anyone think I am a woman, I think it's a lot about the attitude and how I feel myself, it's like masculinity come out on my features through the way I carry myself.

So I think that perhaps that is also something that could help you tone down what you say is a pretty masculine physical look. For ex, I noticed that men tend to sit more sprawled out on a chair, legs more spread out, while women do the opposite. These are culturally acquired stuff most of the time but they happen. Try to have a more ...gentle, dainty (but not overly so) way of interacting with the world and generally let your feminine side shine through.

If you're very hairy you could shave although you might not want to shave your arms and legs as long as you don't want to pass right now, better not to ask for trouble. If your face has dark stubble(are you taking hormones?) then maybe a close shave and very sensible make up to help cover the signs of stubble would also work.
Not bulking up would also help.