The swim cap may force your hair to shift and pull your hair down, so you may wish to tie your hair a little higher than you would expect it to be positioned in the cap.
Consider coating your hair with a thin layer of conditioner. This will make putting the cap on a lot easier.
Wetting the cap may also make it harder to put on––it depends on the type of cap used.
Positioning the cap near your ears is mostly based on personal preference. Some people like to cover their ears completely with the cap, especially if they are racing. Others like to cover half of their ears, while some don’t cover their ears at all.
Remember that you can position the cap around your ears in whatever way is most comfortable for you. You can tuck your ears in, leave your ears out, or cover only a portion of your ears.
Your friend should be holding the cap on the sides, with the water inside the cap.
The velocity from the drop will cause the cap to fall on your head (because of the weight of the water) and the cap consequently will fold over onto your head. Be aware that this method doesn’t always work on the first try, and the results can be rather inconsistent. More often than not, adjustments are necessary.