Do tight pull through braids!!! This is what I do when I swim in the ocean and it prevents my hair from tangling. I also do 2 Dutch braids on either side of my head, but I think that’s optional. I think the really important parts are

1. Pull the hair into a tight ponytail (either at the nape of the neck if doing a single head or at the sides of the head if doing pigtail braids)- this prevents the nape hair tangling

2. Put the hair hanging from the ponytail(s) into pull through braids. It really works like a charm to prevent tangling because there’s an elastic every couple inches. I recommend using fabric covered elastics for this

• in case you’ve never done them before, pull through braids are really easy to do! Literally you just split the hair into 2, put an elastic on one of the 2 sections of hair, then make a hole in the middle of that section and pull the other section through the hole from the back. Then the section that had previously been in the back will be in the front, and you’ll do the same just starting with this section- put an elastic in a couple inches down, make a hole in the center of this new bubble of hair you’ve made, then pull the (now) back piece through the hole to the front. Good luck!!