Bottom two pair

How do you play these hands? Say you get 3s 4h out of the big blind and check your options, and the flop comes Ks 4d 3h. What do you do?

I used to play any two pairs as if they were the nuts. After being cracked a few times by people drawing out, I changed it up.

Now I play them as if I have the nuts and am trying to trap. For instance, rather than making a 2x pot bet (or pushing all in), I make a half-pot bet. Sometimes I'll go ahead and bet the pot to try and weed out the fish, but rarely do I overbet. Do you follow a specific strategy for bottom two pair?

Also, if you are faced with a raise with bottom two, based on whatever circumstances you choose, what do you do?

Hmm, I don't know why you would bet 2x pot or push with any hand, at least as a general rule for playing the hand. There are times to push, given stack sizes, blind sizes, opponent's interest in the hand, draws on the flop, ect, but not just because you have a certain hand.

2 bottom pair you have to play fast; bet 1/2-full pot because you are likely ahead but very vulnerable. For example, if someone calls you with K9 and the turn brings a 9, your two pair is nearly dead. If you get resistance, you have to determine whether you're up against a high pair (KQ for example might raise you saying they have good kicker) or something more (K4/K3).

Like NineLions said there are way too many different situations in poker to say "play your bottom two pair like this". Personally I often play bottom two like TPTK, very aggressively and very cautiously at the same time.