1. Spend as many points as you have to on your Seer Council to make it a menace on wheels. This is one unit about which you shouldn't be concerned with being frugal. It's the backbone of your army, moreso than in regular Ulthwe. Spend the points and give it serious muscle.
2. Use Eldrad Ulthran whenever you can. Normally I don't advocate the use of special characters as a perennial strategy, but in this case I do. His role in the Seer Council as a psyker will really matter for the survival of your Strike Force, and for USF in particular the ability to redeploy really helps a lot. Again, don't be afraid to drop seriously big points on that Seer Council (which adding Eldrad will necessitate that you do).
3. Drop the Wraithgate as early as you possibly can. Unless you have a very specific strategy in mind for it, don't wait till the last minute to put it into play. Reserves can start arriving in turn 2, so don't wait. Getting hung up on dropping the gate deep in enemy territory can sometimes make you hesitate, which isn't necessary.
4. Take at least two Wraithgates. You will often need the options for deployment.
5. Forget using the Spear of Khaine. Though I encourage players to spend lots of points on the Seer Council, the Spear of Khaine just takes too many points out of the list to make it practical... especially for the ROI it offers. Try it for fun if you want to, enjoy it, but don't even dream of making it a regular part of your army.
6. Make a point of creating as many distinct units as possible. Half of your units, rounded up, will start in reserve. The more units you have, the more you get on the board during deployment. Do this by splitting up units of War Walkers and Vypers, for instance, making each an individual unit rather than just making a single group.
7. Anything infantry you have which fires heavy weapons should be part of the initial deployment. If you wait and bring them on as reserves, you'll lose a turn of shooting because when they arrive they are moving, and therefore can't fire a heavy weapon. Think about it: If you keep your Dark Reapers in reserve and they arrive in turn 2 you still can't shoot with them until turn 3, which is almost half the game -- and that's if they arrive in turn 2, which is far from guaranteed.
8. Don't ever forget to cast Fortune on your Seer Council. A 4+ invulnerable save is a good save, but being able to re-roll it will make your Seer Council almost unkillable... and you want that advantage.
9. USF lends itself to staying back and firing from a distance in a tight cluster behind cover. Be prepared for deep-striking units by keeping something in your deployment zone that will quickly dispatch enemies which arrive out of nowhere. Your Seer Council should be able to accomplish this.
10. If you are playing a "shooty" USF army rather than a "assaulty" one (which is what you'll likely do, as USF isn't best suited for assault-heavy lists), you'll do most of your serious damage in turns one and two. Don't hold back at all. That's your window of opportunity; any later than that and you will have racked up enough casualties that your ability to do harm will be tapering off. Crippling your opponent early doesn't just get pesky enemies out of the way, but it also demoralizes him and makes him rethink his strategy, which will often cause him to make a lot of mistakes.
11. Remember that most people don't know what USF is capable of. In fact, most people barely even know the rules for USF. Make sure you use the element of surprise.
12. Don't take any crap for loading up on "cheesy" weapons such as Starcannons. Remember: You have to start half in reserve, you can't take any heavy tanks of any kind, you can't take any Wraithlords or Wraithguard, aside from Dark Reapers you can only take one Aspect Warrior unit and if any of your precious units (including your fat Seer Council) loses even a single leadership roll, they leave the table without passing Go or collecting $200. With this many handicaps you're entitled to use whatever you have to get any kind of advantage. Those who don't like it can just suck it up.
13. USF really doesn't get off the ground below 1500 points. You can do it, but the sweet spot is actually 2000 points and over. USF is one of the few Eldar army lists (hell, one of the only lists period) that continues to get better between 2000 points and 3000 points. But below 1500? It's hard to turn the engine over. It's too expensive and resource-heavy to make the magic work at that point, so switch back to Ulthwe or Vanilla at that point.
Hope this helps and encourages you kids out there to give USF a try!