Gail,
On the hull topsides, the Poli Glo method (cleaning then sealing) has worked for us. The Poly Glo cleaner is mixed in a spray bottle. The cleaner is then sprayed onto a small area of dampened gelcoat surface. I used a scotchbrite cleaning pad to scrub the surface. Rinse and check if its still chaulky.When you're finished scrubbing, the surface is allowed to dry for an hour or two. Then the Poly Glo finish is applied. It takes about 5 - 10 minutes for each coat to dry. For us, when I finished putting on one coat on the hull topsides, it was dry enough where we started to go around with another coat. 5 - 6 coats are recommended. A sheen develops after about three coats. ymmv.It took about 4 hours to clean and treat our Hunter 25.5 including drying time. During that time, the entire exterior of the boat above the waterline was scrubbed so that time included a lot more than just the topsides.Poli Glo is very slippery and not for underfoot. Be careful where you use Poli Glo as it is not suitable in the cockpit, the deck or anywhere else you might want to step. For those areas, I've used Johnson's Future Acrylic Fkoor Finish. Good traction, seals, gives a nice sheen and is easy to clean.