I'm certainly no expert but I can give you a few tips. Unless laying over new glass that has not fully cured then I would clean, sand and rub down with acetone before starting. Flow coat is easiest to use by brushing and a softer (more expensive) brush gives best results and less brush marks than the $3.00 throw away ones. I have had little luck cleaning them so I use a new one every 30 mins or so. Don't skimp on application thickness if you are only doing one coat. I slop it on then brush it out.
If you are not running matting or carpet over it you will have to look at the nonslip nature of the surface. You can sprinkle on sand or glass microbeads before it goes off or sprinkle sugar crystals and after its gone off (next day)hose it and they melt leaving a nonslip surface thats easier to clean and softer on the feet.
If your glass is in good condition another alternative is to use an acrylic co-polymer deck paint like tredgrip. It can be applied straight onto glass and is a soft nonslip surface
http://boatcraft.com.au/informationp...nformation.htm
Many cruising boats use this over older existing fibreglass decks.
Cheers
Neil