1. since a standard action can be used to take a move action, can this feat be used twice in one round (once as a move action, once as a standard action to take another move action)?
2. if so, can both bonuses be used in a single attack against the same creature? in other words, do the bonuses stack?
1. Yes
2. No
From Glossary
"Multiple competence bonuses don't stack; only the highest bonus applies."
You are your own ally.
This is another one of those areas where "You are you own ally" doesn't really make sense (people need to stop reading/quoting that FAQ in partial, and need to read the whole thing).
Does it really make sense that during combat you could tell yourself, "You should swing your sword in such and such manner" and give yourself a +2 bonus to hit?
As the the original question, you could use your move and standard to give two separate allies a +2 each.
"For your ally to benefit from this feat, you must be able to clearly see your ally"
So it only works on yourself if you're fighting in front of a large mirror.