Nicky,
You honestly have a really good starting point! When I saw your first picture, and I'm NOT saying this to be nice, I thought you were FtM. Your features are pretty feminine; you have real potential hon; I looked no where near as good four months in, I can't imagine that many of us did. I promise I'm not being nice for the sake of it (like some of the girls here do) when I say you definately have potential! Here are some tips though:
Makeup: Makeup was key for me in finally being able to pass. I don't know how much you know about it. If you can manage to scrounge up the money, it might help to go to a a store like Sephora and just ask for some help choosing a good foundation, eye palette, etc. I've found that a lot of nicer cosmetics are easier to apply, which really helps! Don't overdo the makeup either-my rule is that if I have a bold eye, no bold lipsticks and vice versa. As for contorting-focus your blush on the apples of your cheeks, and be sure to hi-light too. Evening out your brows will help a lot. You have feminine eyes, but a bit of mascara and eyeliner would really make them pop. Just remember: When you're starting out, keep it subtle! Nothing tends to out a beginner like overdone makeup or clothing. Don't go for dramatic until you've mastered your basics; I'm wearing hi-lighting makeup in my avatar here, but it's feminizing makeup, not nightclub makeup. I'm not sure if you're wearing any in your last picture; if so, you could stand to use a bit more, but more carefully. If not-it just takes practice. Makeup is probably the best way to ensure you are gendered female, even when you aren't wearing a dress or skirt.
Clothing: It's hard to find a style that works for you when you're just starting out; I'm not sure what kinds of dresses you've been looking at, but for girls like us finding a flattering silhouette is key. I always tend to gravitate towards A-line dresses with a subtle flaired skirt; subtler colors are better, especially dark ones. Go for dresses that accentuate your hips, and won't make it too obvious that you're padding your bust. Stay away from sheath dresses or really anything that hugs the entire body so closely. They are not flattering at all; a lot of girls go for those early on, and it's usually a bad idea. Anything a bit looser that you can belt is also a great idea. Consider darker tops; they draw attention away from the shoulders, arms, and bust. Make it your own though; eventually, you'll settle on a feminine style that suits you. Right now I'm in the middle of a "vintage goth" phase...it feels good to have my sense of fashion back, hahaha! I really love that hoodie; you're off to a good start!
Other tips: Padding your bust is key. Finding a bra that fits, and a nice pair of falsies can really help you pass. That's not something I've perfected yet even after three years, it's not easy-but you can always look that up. Consider a darker wig-the one you're wearing doesn't look totally real, and a fake looking wig can really give you away. It's not bad at all, but if you're concerned about passing, the wig is something you need to get down. Have you considered wearing something darker? Your natural color is brown and your eyebrows match that-why not go for something a darker and more natural color? A bit of nail polish can make your hands look smaller if the color is on the darker side (a trick I figured out on my own). Besides that-how is your voice and body language? Even posture is key if passing is your goal.
All in all, you're off to a really good start, and if you have a question or anything I'm happy to help...the only thing I don't think I've fully figured out is hair

Another piece of advice-I saw your post on FFS. You should wait-you seem to be around my age when I started HRT, and I thought I was going to need it for a while, but eventually the hormones did their job. I'm just past my two year mark, and in terms of my face they've done a lot. Don't commit to FFS until you've been on hormones for much longer. It's insanely expensive, and you might not even need it.
Best,
S