Welcome Ryan
Cotton Tree is a great kiting spot, prevailing wind is NNE-NE which works well here.
Best time is at high tide slack and just after the high tide starts to run out, about 3 to 4 hrs after the high, the current is strongest and you start loosing water depth on the sand bank. I recommend if you are not on the board yet, drag over the channel onto the bank and move 100m or more away from the beach. You will have a huge knee to waist deep area you could practice your water starts etc with a very safe 400+ meters of shallow water down wind of you.

I saw a Noobie try to swim his kite and board back across the channel during max current a few weeks ago, he lost 200m before he could get across.(I was on my way to help him whin he made it across to a spot he could stand)
You'd be better off practicing dragging with your board the first session if you are not up & riding yet, this will allow you to easily drag back to the beach at the end of your session when the current is a lot stronger.

A few weeks ago there was not a lot of beach at high tide but there were a lot of other beach users, I ended waiting about 15mins for another kiter to arrive rather than do a self launch on a crowded beach - Think safety first, we don't want to loose this spot!

Chat to the other kites etc for local knowledge, we are all very friendly.

Happy kiting