I'm going to respond with it being specifically relating to Splatoon, rather than my entire art history (just to keep things simple, since I know up-and-coming artists can get overwhelmed by information).
The main thing that helped me with my art was not being afraid of adding too much detail. When you analyze a reference, and draw what you see, well, you're already learning when you think that way. You can stylize it, you can make it funky, but learning all the parts
first before bending them out of shape will give you a better foundation to work with.
Now you may ask, what on earth do you mean by this? See here:
<- This is the first item I ever made the attempt to really try to draw. I knew that this was going to be difficult to replicate, so I used a reference (not this one, but one I took for myself years ago). Looking at this image however, you can already see a lot of details you may have overlooked if you tried to draw it at a glance. Stitching on the helmet, the shapes of the molds, the depth of the goggles, the texture of the chin strap. As it was my first time drawing this I tried to fit every detail I could, while trying to keep the shapes of the objects the same. This is how you memorize what something looks like. Of course it may require some more practice, but that's how you improve.
Don't be afraid to mess it up, either- you didn't learn to read
just by looking at the letters, right? You needed to know what they meant, as here you would want to know what part was what, in order to draw them. Breaking this gear down to parts in order to make it easier to draw is something you can do to help yourself, as you can with just about anything. Separated, there would be a hat, the goggles, the night-vision goggles above them, then the attachment for the goggles, and then the strap. This makes it easier to digest.
Along with doing things like that for gear and weapons, I drew a
lot. Drawing for fun and trying new things here and there helps you gain knowledge as you go, without fully going into "omg I have to STUDY?!?" mode. I had fan characters I liked to draw, and then I had to learn to draw the outfits I wanted them to wear, which was fun. I had to learn to draw Bluefin Depot for a comic I was making, so I used a lot of reference images in order to draw the layout correctly. If you draw anything, using references (such as photos or screenshots) makes it so much easier. Breaking them down will make it all a breeze
That's the more general clump of information I can give when it comes to drawing Splatoon-related stuff. I ended up saying a lot but there's a lot of options for you when it comes to starting out. Remember to keep it fun for you so you stay invested. Never give up!!!