I have been playing NLH for about 2 years combined. I mainly play @ a local bar with a regular .50/$1 cash game. I tried in the beginning to raise the PREMO hands, but would get called no matter how much I would raise. (7.5x-12x the big blind would get a table full of callers. anymore than that and I wouldn't get any action.)
So I have slowly had to change my game to more of a slow play/trapping style.
It has hurt my game tremendously. When I go to the casinos, I raise the PREMOS and get just a few callers. that is great, but playing post flop is where I am having a bit of trouble. Any advice would be helpful. I am looking to get better, I just don't know the right training aides or the correct way to go about it. Any help or advice would be appreciated.

You're asking "How does one play poker". Too broad for anyone to answer. 2 years of muddling through and you want to get better. Good for you. Read everything on this site is my answer. Everything. ((((So you don't like my answer...sorry, I am replying to your question is a similar manner))) But I will try with one aspect of your post.

Slow play/ trap play:
Don't

Raise your premiums PF...plus other hands (very important to not JUST raise premiums). If others join you PF and create family pots...you need to make them pay....each and everyone of them. Otherwise you get a family pot anyway.... without anyone paying extra to draw out on your premiums.

HOWEVER, collectively the more in the pot, the lower your equity. Everybody calling with Q4o if good for you, right? So...

Now, learn to read the board and be able to release hands on the flop. Stop paying off with TP (or overpairs) on MOST boards against a large field.