Always dive with a buddy, spearfishing is very much of a team sport.
2. Learn what to do if there's a blackout - a freediving course is best for this
3. Watch out for boats as they may not be able to see you whilst you’re spearfishing - carry a float and flag at all times.
4. Get CPR training.
5. Never attach your fish to your body - put them on your float/float line, or in the boat away from you.