Here is my short-stack strategy.
First, at roughly 10bb I am in jam or fold mode. This isn't in stone. I go by feel. Sometimes it will be 12bb, sometimes maybe 7bb. Usually when I get down to 8 or 7 bb (or sometimes less) it is because I can get very fussy about what I jam and I should probably be less fussy. This is probably an error in my game. If there are antes, my shove range will be a bit wider but if there are no antes I can take it orbit by orbit as only the blinds will chew at my stack. If I have a mid or low pocket pair I will think about shoving at 14 or 15bb since my fold equity is worth a lot more than my post-flop equity here. Maybe I am wrong to do this but that is where I am at right now. If I am in a very overcally game like a freeroll or a play money game my shove or fold mode will start closer to 15bb. This is because a standard opening sizing of 2.5x to 3xbb won't get enough folds pre, so a standard open size is 3x, 4x, 5x bb. If I open 4x with only 12bb, it is easy to see that I am not very playable post-flop if called (especially multiway) so it is better to just rip my 12-15bb in their faces pre-flop.
What do I shove? That depends on my position. Of course if we are all-in we do not care about post-flop position, but many jam value
hands are better to see the pre-flop action before committing our tournament life on them. There are 3 kinds of jam hands.
1 - Prime hands are a shove from any seat.
2 - Near prime hands (stuff like KJo - not quite prime but dammit we may not get better so hey close enough) usually shoved from any seat but depending on my gut instinct.
3 - Marginal shoves (stuff like mid-low pocket pairs and A-rags, have immediate showdown value ) I want to see the action so will almost always fold them unless I'm on the blinds and the table is weak. Then and only then am I all-in.
Let's say that I am on the SB with A4s. There is only 1 limper, so only him and the BB to showdown with or make fold, and hey, A4s probably competes very well with a limp range. So THEN I will jam. But if there are say 3 limpers, it's too many, and of course if someone else opens, I just lay down.
Jamming a marginal shove hand from say UtG is very dangerous. Let's take our A4s. If we shove that UtG we just give that big stack behind us with A8o an easy call to dominate us. That's why we need to be stronger to jam when we can't see any action first.
Also, I watch the stacks around me, If I have 8bb and the player 2 seats to my left has 80bb, mathematically, he is supposed to call me with ANY 2 cards (provided that he is confident of isolation). In this case I can be 99% certain that I WILL get called. This could be bad because I will have to showdown for my tournament life, but also could be good because he can call me very wide and I have a strong chance to be ahead and double up.
One more thing that I will add. I don't always have to shove my entire 9bb all-in. If I am confident of stealing, a normal
bluff sizing will do. Simple example. I am on SB and it folds to me. I have 9bb and the BB has 16bb and I know that he's a fish who won't attack me back unless he is super strong. Let's also say that we are 1 or 2 felts from the bubble making him even extra foldy. He hasn't acted yet so he is 100% wide. If my standard 2.5x or 3x bluff raise will make him fold, then I don't have to jam it all-in just in case he wakes up with AK. Basic bluff sizing rule often still applies and that rule is: what is the smallest amount that will make Villain fold?