Well, since no one wants to take this on on, I will. My best advice it to get instructional videos. The are available from WGI, DCI & individual corps.
As far as spinning & tossing flag, the basic spins are: drop spin (you drop the falg into the oppisite hand, while the oppisite hand is turned over, palm out), push spin (you push the pole with your hand turned over, palm on pole) and double-fast (aka peggy spin) (you start off with a drop spin, but instead of continuing drop spin you catch pole horizontal with both hands facing up, then continue with drop spin, repeat).
To toss you should start with a wind-up: It's like a double fast, where you drop, flat, but then you bring the pole on around & catch with your left hand on top, right hand on bottm, the backs of your hands should be facing you, take right hand off pole & bring around to shoulder-hip angle with left hand hand, catch with right hand where the silk meets the pole & toss up with your right hand.
I know all this sounds confusing, that's why I suggest a video.
Rifle toss is a little simpler, there are many spins, combinations you could enter a rifle toss with, but basically you should prep the toss by bringing the barrel end of the rifle up so the rifle is straight up & down in front of you, then back down where the butt is on top, the bring back up & release upwards, tossing with your left hand.
Sabre is basically the same as rifle. Just a different feel.
You should get some other basics down with these peices of equipment before attempting tosses.
Can you get someone on the guard at the high school to show you some basics?
Hope this helps!