Hi Welcome to Specktra!
Firstly get yourself some basic brushes. I would choose the 239 to apply eyeshadow, 217 to blend eyeshadows and eye bases and the 187, which is useful for so many things...liquid foundation, powders, blush, highlighters....
Next, I would try a paint, paint pot or a shadestick to use as a base for your eyeshadows. Different bases make the same single eyeshadow look totally diferent.
Also, check out a good foundation for yourself, an exact match for your skintone. This can make a world of difference to your overall look.
I'm not sure if your a newbie to make up or to MAC but one thing I want to say is you shouldn't be afraid to try all the weird and wonderful bright eyeshadows, I was for a long time, now I realise what I was missing out on! lol!
Hope that helps!