I like to concede im still new at this game. I like to raise pocket aces but the last couple times ive raised pocket aises between 4x and 9x the big blind i still get callers which is good but ive come across problems...

Some examples:

First round of MTT tournament, 10/15 blinds im BB, 5 call, i raise to 125, 4 people still call:

flop is 8 6 6, i put 250 into a 500 pot, 2 still call, next card is 8.

I go all in... i get called by a Q 8 offsuit so i lose to fullhouse. The Question is what size bet should i make to not scare them off but not attract these dodgy hands?

Other example:

I raise 3xBB, 2 callers:

flop is 4 10 K, i bet half the pot and guy reraises me so i go all in and he has pocket 4's so he has trips and no aces or turn come on river.

I should also note these are cheap buy in party poker tournaments.