First of all its important to understand, that a loose game is potentially way more profitable than a tight game. The reason, why it often frustrates people, is that they are not prepared to make the nessesary adjustments. In a tight game we can win many small pots without showdown by raising preflop and C-betting the flop, if we get action. This is very easy, and when such a strategy fail to work, some players feel a bit lost and dont know, what to do.
But the answer is actually very simple. If aggression does not do, what its supposed to do (make people fold), then we should probably take a passive or neutral action instead. If 4 people have limped, and we look down at 77 in BB, we should just take a free flop and try to flop a set rather than make a big raise, get called by everybody, and now we are out of position in a bloated pot with a hand, that hate most boards, unless we flop a set. Or if we have raised AK preflop and gotten called by 4 other players, and we miss the flop, we should check and hope to get a free card. And if someone makes a substantial bet, then we just give up and fold.
In loose games we depend more on winning at showdown, and this also require us to play the late streets more often. But the upside is, that when we win, its often a much larger pot. And yes this require patience, and it require hitting boards. Flopping that set or completing that flush on the river. And this is where a lot of people face problems, because they dont have that patience. They have also been told, that "good poker is aggressive poker", and they cant move past this simplified way of looking at the game.
In loose games we should also look to stack off wider preflop. Maybe if we are only 25BB effective with that 77 in BB, and 4 players have limped, then we just jam, and then that will actually get everyone to fold. Or maybe one player call, and then we just play a "flip" against, whatever he limped and then called us off with. Or we participate in a 3-way all-in preflop with AQo, because we are ahead of their ranges. And yes most of the time we will lose that, but when we win, we tripple our stack, and we are in great shape to run deep in the tournament. But this is also something, a lot of people hate, because they think, moving all-in preflop is just "
gambling", and they hate variance and early bustouts.