Support sounds like having a cooler full of potions that increase the other players could be your stick. Depending on your GM, some potions could give a character a minor power for a short time. Like a potion of flight could give a character the "wings" power.
To do so, you'd take thaumaturgy and a ton of refinement for potion slots. Lore should be your highest skill.
Any potion would have a power based on your lore. In a submerged game, that would be a base of power:5. You could take a potion specialization for your free specialization and make that 6.
You get 2 free focus item slots, which translates to 4 potion slots. Each refresh put into refinement gives you 4 more potion slots. You can spend a potion slot to get a new potion or add 2 uses to an existing potion.
Most of your potions should probably be maneuvers, since those can give benefits to others. For example, you can have an eagle-eye-potion that would give a sniper a benefit when shooting at a distance (he gets a free invoke on the "eagle eye" aspect after drinking the potion, which he can use for +2 or for a reroll).
You could go all out for a total of 28 potion slots. You can leave some of them free and use the "potion declaration" rule. In that case, you can ask to have a potion with you that you don't have announced previously. The GM will then give you a difficulty based on how plausible this might be, and you roll Lore to beat that. If you do, you have that potion with you, the potion follows the usual rules (as if you had it with you the whole time). Or you can spend a Fate point to have the potion without a roll (if you go for the roll and fail, that option is void, though you can use the FP on the roll).
To give a character a minor power, you can do the same, a maneuver potion, but instead of using the free invoke for a +2, you use it to pay off the temporary power (Your Story page 92, yellow box). Some GMs might not be willing to allow free invokes instead of Fate points, so you'd have to ask your GM if they are ok with it. We've had quite a bit of discussion about this on the board here as well.
Ok, I think that's enough wall of text. If you need some more information or clarification, just call me. I'm in the book.
No, wait, that was someone else.
