Ok im 13 yrs old i took on scuba diving with my dad 2 years ago. i have my own spear gun. and i just bought the cressi-sub garas 2000 free diving fins. I want to start free diving more then anything right now. i can do 4 laps in my swimming pool under water with 1 breath with fins. but when i time my self on how long i can hold my breath its only 53 seconds that’s very bad. What can i do to make me hold my breath longer please help thank you!!!!

Work on slowing your exhale. Hold your breath until you think you’ll burst, then slowly let out just enough air to ease the discomfort. Repeat. Whatever you do, do NOT hyperventilate. It could be the last thing you ever do.
http://en.wikipedia.org/wiki/Shallow_water_blackout