Inside skin is sealed with thinned epoxy.
Blocking Installed for the handle, fin, lease, and vent.Marked the locations of the blocking on the painters tape on outside of the board.
Properly feathered rails with a sharp transition marked with painters tape. This tape (shown) is very important for knowing when to stop shaping the top. The rails should be shaped 100% in the area near the tape. Even sanding this area can mess up the crisp transition from top deck to rail.
You can seal the inside with epoxy thinned with denatured alcohol. This step is optional as it adds a bit of weight but is nice insurance if you ever forget to tighten the vent. It is important the there is no epoxy on the top of the fishbone or the flat area you made on the rails or the adhesive will not stick. The shaped area was protected with green painters tape while the inside was sealed.
Clean up any drips that might come loose in the future.
Clean the interior and flip the board and give it a shake to make sure you have everything. Compressed air works really well with the board inverted.
Take a picture of the inside of your board as it should be the last time you will see it!