Getting back into the groove

just picking pitching back up. now 17 havn’t thrown heat in nearly 2 years but was a year round player since 8, wanna know any precautions I should take to prevent injury when starting my preseason (for next season) training. Thanks a lot. Any specific advice to get myself right back up to top performance again?

Work on building lower body and core strength.
Work on your mechanics.
Have fun!