Use a team you see fit, if you like...
fast go with:
-Guy, Kakashi
-Lee, Guy
-Kakashi, Guy, Lee
-or a little switch up with either neji or naruto
Slow but powerful go with:
-Shikamaru, Choji, Tenten
-Tenten, Hinata, Sasuke
-Tenten, Shino, Kiba
-really, it's pretty self-explanatory
Now... once you have found the perfect team that you see fit, practice with them, in Player vs. CPU. The strategies are as follow:
Fast:
As soon as the round starts you need to dominate, Subsitution jutsu is your friend here so you can quickly reverse it and get some quick hits in. Most of the jutsus aren't worth using, but with somebody like lee, the gates come into play. You slowly get hurt so it's not smart to get his technique off until they're under or almost at half health. Never let your opponent regain healt/chakra. Just double click o and get over there quick, make sure to get in some shots to get them out of guard... and lastly, ooo combos won't do it, you might need to know everything they an do so you can add in alot of extra hits and throw.;D
Slow but powerful:
This may be your cup of tea. If so read on. With these fellows they're relatively slow to get going, and many of the secret characters you will unlock are too. But how should you use them? Easy! First, when building a team it may be good to put in one fast person to pick up the slack. But mainly, these are about their jutsus, and how to get them off. Thir combos are usually to slow to get off leaving you vulnerable, so... Tenten comes into play, she has a valuable "tool summoning" jutsu (up,up,o) which lays alot of tools on the ground, or if you ever have some tools you picked up, this is the key. Once ypu have full chakra make sure to change to your tool. Now, throw it and run! Click triangle and and as soon as the tool is done make sure to hit them, this leaves them vulnerable letting you get a solid hit in. This strategy is pretty deep and I'll stop here.
Building a team:
Build it around stats. Well what do you mean stats bonsly? OK...
-A fast person is always good
-Someone who can heal but isn't to bad *cough*Tenten*cough*
-A slower but well rounded person
That makes a good team, and then make sure to see their skills, for instance, Sasuke has Chadori which lowers an opponents health by 33%.
That wasn't to hard was it? Man that took long, oh well, good luck!
P.S. Gaara always blocks so you may break my rule about the Lee thing. Start with Lee and get off his technique as soon as possible! Then just try and get a few more hits in but overall, Garra is down a good bit because Lee has a skill that lowered Garra dpwn 33%.

Alrighty, now bring it up with a medium paced peson (Sasuke) and now Garra should almost be dead (Sasuke also has a skill that lowered Garras' health 33%). And if you really wanted, you could get another character that has a skill that lowers health so you auto-kill him. But what's the fun in that>
Hope this helped!
~bonsly1994