I am a tournament player and will discuss playing pps mainly in tournaments and SNGs, although I will also discuss applications to cash games. I will mostly discuss preflop play.
Basically, there are three main ways to pay small pps. You can semibluff allin preflop, which is always a somewhat thin play, whether it is a pushbot, 3-bet, 4-bet, or 5-bet.
You can set mine, which is often very profitable, and I will discuss what situations this is best. In general, getting good immediate pot odds is reason to call, and more important than implied odds. Set mining works better deeper and in loose passive games. You also would prefer your opponent(s) have strong hands when you set mine. Obviously, if you set mine, you are not always folding if you miss the set.
The other approach is to open a small pp normally, generally from mid to late position. In this case, you play it more or less like any other marginal opening hand, and usually cbet flops you miss, and “play poker” from then on.
In early position
A small pp in early position with 12-30xBB is usually an open fold. The exceptions would be if the table is very loose passive and there is a good chance of a multiway pot or if the table was so tight you had good stealing chances.
If you are relatively deep with a small pp in early position, it is usually an open unless it is a tough table. Many online cash games are tight enough now that it is better to open fold a small pp in early position. In loose games, such as live cash games and early in most tournaments, it would be really bad to open fold a small pp deep because of the potential to win a big pot if you hit a set.
It is possible to limp a small pp in early position to induce a multiway pot. If you are deep enough, you can often limp/call a raise and maybe get a multiway raised pot. This can be good for set mining.
Limping small pps can work well in soft loose passive games. Some regulars will limp small pps and only that because they are so good for limping. There is a problem doing that in relatively tough games such as mid stakes SNGs. Other regs can raise the limp and take down the pot the 7/8 of the time the limper misses the set. If you are going to limp in tougher games, you need to often play back on low flops where you miss the set. Also, probably better to sometimes limp suited connectors or big hands so you are not so predictable.
Early in a tournament, if you are usually raising 3xBB or more, it is possible to raise like 2.2xBB with a small pp to induce a multiway pot. Many players open small from the beginning, and most opponents will not notice it is not your usual sizing.
Getting allin preflop with small pps
You can usually open shove or pushbot a small pp in early position for 10xBB with ante. Without ante you need to play tighter. 66 is somewhat more valuable than 22, but the difference is not that great, since you are usually getting called by higher pp or overcards to either pocket pair.
The later the position, the more BBs you can shove. It is possible to raise rather than shove for 15+x BB. However, small pps play well for an overshove. They don’t play well postflop shallow if you get flat called: you generally have 3 overcards. However, they have good equity allin preflop, as they often get called by overcards where they are the slight favorite. For example, it is a reasonable play to open shove a small pp for 20xBB from cutoff or later.
You can usually shove over a loose late position raiser with a restealing stack with a small pp. You are should usually fold to an early position raise with that sort of stack. The exceptions would be if the raiser was very loose and there was a good chance he would fold. You could also set mine to a miniraise in the BB short stacked and maybe overcall or squeeze shove if there is a multiway pot. In general, you need a read that the raiser is loose to reshove with a small pocket pair.
In a tournament or SNG, you can sometimes 4-bet shove over a reraiser with a small pp. This is pretty thin, so the player has to be 3-betting light or you have been opening a lot or the action is in late position. At higher stakes, it is possible to 5-bet or 6-bet shove a small pp as a semibluff. The pp has reasonably good equity against a calling range including AK/AQ. For this to be playable, both players have to be reraise bluffing a lot.
In general, you should not use a pp to reraise and fold to a further raise. It is not a good hand for that purpose, because it plays poorly postflop shallow and you have high cards to block or make less likely big hands your opponent could have.
Flat calling with a small pp
It is usually bad to flat call a raise HU with a small pp and less than 30xBB. You aren’t really getting the price to straight set mine. If the table is loose passive and you expect a multiway pot it may be OK. Deeper it is marginal whether to call. You either have position or a discount in the blinds, so a call may be fine, but you aren’t usually going to get enough profit just set mining.
You should almost always overcall a raise with a small pp. The reason is you are getting good odds to set mine multiway. Plus you either have position or a discount in the blinds. There are some times when pushing is better. If there is a very high probability that a player to act will reraise, that might make calling less attractive.
In tournament and SNG play today, it is almost always correct to at least defend you BB with a small pp, even HU or very shallow. That is because you are getting something like 4.5-1 heads up. You are 7-1 to hit a set and can expect additional money to go in if you hit.
After a limp
You see less limping now, but if there is a limp or multiple limps before you act, it is almost always better to limp behind than to raise. Many player tend to never limp behind. However, with a small pp, you want to keep the money deep and the action multiway. You also do not want to reopen the action. You don’t want to give someone who was trapping a chance to 3-bet and blow you are your hand. You want to see a flop against big hands and you hope to hit a set and win a big pot. Also, if you raise, someone could cold 3-bet. When you limp behind you can often call a raise maybe multiway and maybe in position.
In loose games
Live low and mid stakes tournament play and live cash games are often loose passive. Many players want to see a flop. In this sort of game, it is almost always to play a small pp and usually to play it passively preflop. The expected profit you make by set mining multiway and deep against mediocre players in enormous.
Most people think small pps are more valuable deep. This is generally true as you have more implied odds to hit a set. However, if you are very deep like 150+xBB, as early in tournaments or in some cash games, there are also negative implied odds. You almost always do want to play pps deep and they are very profitable. However, if you make a set, it is likely bottom set. If someone makes a higher set of maybe a straight, they will win a very big pot. Sometimes it is necessary to pot control postflop rather than try to get all the money in with your low set or boat, particularly in tougher games where opponents are not likely to play huge pots with hands you beat.
Some of the approaches I have outlined may seem counterintuitive to some. Often the best approach to playing a small pp is a passive approach or calling preflop and usually folding if you miss the set. This contrasts to the currently popular aggressive approaches, which work well in many situations.