There are many different ways to blend with acrylics. Here's the most common 1. Use Water 2. Work thick 3. Work slow and in small areas working your outward 4. If all else fails be lazy and use a slow drying medium
Acrylics clean up loads easier than oil paints, that's for sure! And they dry pretty quickly so it's easier to layer them.
But the bad thing is, they dry pretty quickly so it can be a pain if you don't work quickly enough. You might want to invest in some retardant. As for mixing the colors themselves, it just takes some practice getting used to the particular paints you bought. Depending on the pigment quality of the paint, you might get different results. I'd recommend maybe making a color wheel out of your paints and see how they mix.
Don't know so much about the "not blending" bit, haha. Mine blend perfectly fine on the palette or the format, though it does make for a longer process when working up a piece any larger than 18x24". I switched to acrylics a few years back, and I focus on an extremely restrictive palette. Keeping with tones similar to the conventional red, blue, and yellow and backing away from distant pre-mixed colors is a good approach. Everyone has a different approach to painting with acrylic, but if you want to knock out a painting pretty quick, mixing directly on the canvas has worked wonders for me. It forces you to work faster, and you can get a lot done within an hour if your paint dries fairly quickly. I personally work with 3 brushes, a large brush for an under layer plane, and then I jump on top of that with a mid-range brush once that's dried, and then maybe later tighten up things with a tiny little brush. Not to mention you can define planes of color however you feel that you left behind before as you go along with a piece.
im not the best tip giver but acrylic does dry fast so if you want to blend a certain color and need a good amount of it, its best to do it via palette or what ever you are using (i use tub aware lids). you can blend on to the picture its self, and get neat textures from it.
work with your largest brush as much as you can, for all those giant areas that need to be painted i like to use a sponge. you can overlap your colors but keep in mind yellow is transparent so if your trying to put yellow over other colors you already have down you will need to layer it like crazy or apply thickly just to get it to be yellow.