You're best bet is to enroll in a gymnastics class. Most people automatically shrug off this advice, but half hour classes once a week may be as low as $10 each. It's worth looking into because you'll learn the safest, most correct way to tumble.
If it's not that option financially or you don't have a facility close, let me know what kind of space you have to practice in, what kind of mats, etc, and I can give you some conditioning drills specific to a back handspring that you can do w/ out a spotter. Of course, when you try the skills full-out you'll definitely want a qualified spotter.

Don't try it at home if you've never done it! That's extremely dangerous. Tumbling could take years to learn also. Your best bet is to enroll in tumbling classes.

If you are a basic tumbler . . . focus on the basics. (rolls, cartwheels, round off, bridge kickover, walkovers, and most importantly the handstand.)

Take a tumbling class and work on your basics first. Do not go straight to a BHS without learning your foundation skills. Without this strong base if will take you two to three times longer.

Do not go in demanding to learn a BHS follow the proper progressions and you will be more successful, learn faster, and be safer.

Start now to be ready for May. Every week counts. If possible go to tumbling twice a week. Gymnastics success is strongly reliant on repetition.

Good luck!

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work on basics at first. the handstand is the most important thing.

i would then enter a gymnastics class. there the coaches or trainers will help you work on achieving ur backhandspring ur tuck and then skills more advanced like layouts and fulls.

MAKE SURE U ENTER A CLASS THAT BEST SUITS THE SKILLS U HAVE!!

Well what i do is stretch out alot.
Do bridges if you can and ask someone to stretch out your back.

Yes basics first.
Try jumping back onto a mat which will firmilarize yourself with the backwards motion.

u start backtucks in level 5 or 6 so dont try it and make sure you get ur coach to try and help you with the handspring!