how to play marginal hands OOP?

Let's say I have AJ,AT,KQ,TT or other marginal hands in the blinds in a NL game. The button open raises. I know that I beat his range. But I also know he will only call a 3bet or make a 4bet with a range that beats my hand. So I don't think 3betting would be a good idea, because I will turn my hand into a bluff.
If I flat call, how should I play after the flop? I will miss the flop the majority of time and I will be OOP. I don't think c/f or b/f are good options. What is better? c/c or c/r?

Your reasoning is flawed: if he never calls a 3-bet or 4-bets with anything but the optimal nuts pre-flop (a hand that beats yours), this is a case where actively defending to avoid going to the flop is best.

Against such an opponent, I'd raise with ATC because you always know where you are at and since he is stealing from the button, he is way more likely to be holding ATC himself than TT-AA, AQo+.

Against a total nit, I'd say fold. Agaisnt someone who might be loose/agressive in the blinds, calling here with a hand range you know beats the majority of combos he'll show up with is bad because you are first to act postflop and are not guaranteed to be payed off if you hit or you will bet into an AA that was waiting for a 3-bet.

But if he has something like A5 and I have AT I want to let him see the flop. If the flop comes with an Ace I will win extra money from him, especially if he is bad and can't fold top pair.

Why then a lot of coaches and good players recommend to only call with marginal hands in that situation? I preffer to 3bet with 68s, 78s, 22 rather than AT,JJ,TT,KJ,... I don't want to turn a hand like TT who has showdown value into a bluff. Of course, it's simpler to 3bet with TT and then fold because you know you're beat, but you don't maximise your winnings in this mode. And I am not going to play fit/fold after the flop, that's why I am interested what line is better(check/raise, check/call and reevaluate the turn...)

Yeah, but if he folds everything except the virtual nuts, the money you make from him folding every time he folds outweighs that.

I can't 3bet with ATC because he will notice this and he will play back. In my first post I said he will only call my 3bet or 4bet me with a range that beats my hand. But that doesn't mean he will always do this. Maybe I had a very tight image. And that tight image will make him fold a lot of his range. Or my 3bet% was very low until then. If I 3bet him 2 times in a row he will notice this.
I made this thread because a lot of good players recommend to just call from the blinds with marginal hands not only against the player I described in my posts, but against any decent player. And I don't know how to play postflop. I suppose you don't just play fit/fold. I think the reads are very very important in these situations.

So, 3-bet him 3 times in a row (and c-bet every flop), until he thinks you are insane. After that, only 3-bet him with really good hands and profit from the fact that he'll call with dominated hands.

What level are you playing at? This matters a lot as you can win a lot more pots OOP against worse players. This questions really depends A LOT on who you are up against (not just good or bad but across the board).

And like vanq said, 3 bet atc if someone is only calling if they beat JJ. If they adjust you can do and stack them with a decent hand. Not a bad thing if someone thinks you are a maniac in these situations, just know they think they and you can get them to make a big mistake on later streets when it matters.

What Vanquish said. Also, you haven't once mentionned position or the ability to have the opponent make a mistake. If he has A5 and you three-bet him and he calls, he makes a mistake. If you three-bet and he folds, he doesn't make a mistake but neither does you since you have gained his money, have avoided going to the flop and playing out of position. Having an opponent fold instead of going to showdown in a marginal situation is good, especially in blind defense.

I'm really not into "slowplaying" or "sangbagging" a somewhat crap hands while defending my blinds against a nit whose bet either represent the virtual nuts or nothing.

Also, Paulwaal, there are a lot of reasons for raising: putting more money into the pot when you're ahead, have the opponent fold by winning outright, represent a stronger hand, etc.. Gaining information is the least important reason and should never be the sole reason of an action. Raising to see where you're at means that:
a) You always value the reaction of your opponent as absolute, wich is a mistake.
b) You did not rely on external information (image, previous lines, hand ranges) before getting into the hand, wich is also a mistake.

First off....the better of your options is clearly checkraising (on flops you miss i assume you are talking about). Check calling with air oop is one of the worst things you can do. Any competent opponent will be able to outplay you in position and you will be burning money by doing this. By checkraising with air and showing down hands sometime where you have nothing you will be able to get paid off a lot more when u actually have a monster and u checkraise because villains will not give you enough credit.

All of the above are great suggestions and my suggestion is to not do the same thing every time. Sometimes call, sometimes raise, sometimes check/raise.

It is very read dependent on the button player as well. IF they are tight and have not tried to steal the blinds in the last 10 opportunities, chances are they have something. If they are constantly raising from the button, then you know they cannot always have a hand.