I used to have hair to my waist when I first started diving and my solution was to use a heavy conditioner the night before my first dive. The day of I would use the conditioner and pompade gel I would then braid my hair. At the end of the dive day I would first spray my hair with detangler (you can purchase it in bulk at the beauty supply stores or some hair salons). Each night after my dives I would shampoo with heavy conditioner and start the process all over. Kind of a pain in the rear but it beat the cutting option. Besides it still gets tangled even if it’s not as long :( Seems like anything longer than a man’s cut tends to tangle. Hope it helps you as much as it did me :)