can somebody explain traditional painting to me

I'm not AMAZING at paints or anything but I've recently dabbled in acrylics so maybe I can lend a hand? First though, if you're using cheap paints, that's the biggest struggle people have is getting the student-grade paints (like Liquitext Basics, which are absolutely abysmal to work with). The pigments don't tend to match each other well and it's just bad. I bought a set of Winsor & Newton, 10 Galeria acrylic, that has warm and cool versions of red, blue, and yellow. Also a green, two different browns, and white. I had to purchase an extra tube of yellow because these were far too translucent for certain uses, and a middle grey for it too, but that pack actually got me really far in my destination.

Acrylics are cool because if they're mostly straight out of the tube (I add a little bit of water to help with mixing but not much) they're mostly opaque so any mistakes I make are painted right over! I have not had this luck with yellow... but mixing yellow with my original color works really nice for brightening/lightening my hues along with white, so with a bit of water and layering, I pretend it's like a yellow-white Screen or Overlay layer and work from there. Mix up a matching dark with your dark blue or brown and more water and paint small translucent layers (waiting to dry in between), to fake Multiply.

That aside, if you can wrap your mind around single-layer art digitally while having a brush on normal mode with pressure/size = opacity, it's actually not a horrible transition rrom digital. But if you rely on color modes and layers, it's hard. I miss undo. :,D But practice a bit on one layer digitally, give yourself a limited palette and try to mix it up with only a very basic brush (round + opacity / size = pressure) and the picker tool. Maybe even mix colors on the side of your canvas?

I know you said no youtube videos, but I actually learned a lot about layering acrylics from watching videos by Lunumbra on instagram. Since she paints on Pokemon cards, she extends/paints stylistically and it's a little easier to bridge the gap than watching someone use traditional paint in a traditional style. She doesn't explain anything but maybe watching how she blocks in colors could help?

K so i'm no pro at painting (and I mostly do watercolor stuff when it comes to traditional stuff) but i think i can drop a few tips

One of the ways I like starting off paintings is by laying down a base color for the area/thing i want to work on so i get the general idea where everything is going to go before i start layering on darker tones. With acrylics I start with a mid tone and work my way from there and for more cell shaded/harsh tones I map out where I want them to be before painting them.

Also a general thing you should practice regardless of what paint you use is paint mixing. Especially since it could help out with doing shading, transparent effects, making colors you don't have, and so on. I'd also say it's important since paint doesn't always behave the way you expect it to. depending on the brand or even the color paints can be thicker, more watery, easier, or harder to mix.

 Some Examples of my stuff:

If you're really struggling with how to approach/color something make a thumbnail or rough sketch of the piece to figure out what works and what doesn't (you don't even have to use the same medium! I do mine with markers or watercolors)

Practicing with acrylics can be hard bc it's time consuming and the materials can get expensive, but if you can get your hands on spare paint or tiny canvases try messing with those. Also even though the paper does buckle a lot i sometimes straight-up use and practice with acrylics in there w/o primer or gesso. If you don't have access to paints outside of class, maybe ask your professor if you can take some paint home (i've done so before with little sauce containers and my teacher was really chill with it. Just make sure it's secure and/or you don't spill it). Even though craft paints work a little differently than the paints you'd use for a canvas (craft paints are more watery and in my experience dry with a grainier texture) but they're much cheaper and easier to find and are still good for learning

This might not be the best tip for practice because it's pretty expensive, takes up a lot of time and it's a little different from regular painting but I picked up a few techniques from painting figurines. Mostly with paint mixing but i've also picked up how to do certain effects (ex: gradients, using shading to bring out 'flatter' areas)

hope this helps!

I'm definitely no expert but a lot of the traditional stuff I do is in acrylics so I might have a few tips? 

It's been said already but it's often good to work in layers, first blocking in the shapes and then slowly building up layers of highlights, shadows and texture. 

One thing that has been helpful to me has been practicing the types of textures you can do with different brushes and finding which ones work best for the style you are wanting.

Using blues and purples can also be a good alternative to using black in mixing dark shades, since black can sometimes make a colour look too muddy or desaturated.

I haven't tried it too much myself but I have heard that fully painting the canvas/paper a solid colour such as red, or yellow ochre depending on the mood of your painting. It can really help prevent the optical tricks that a pure white canvas can have on the colours you are using.

Using water to thin the paint can work but be careful to not add too much since on some paints it can effect the binding and make the peel or flake. 

Ooh thank you all, I'll def try the tips when painting next time! /o/