Long exposure

Any tips on getting a good long exposure shot at the beach? I did it once before sun set and didn't like it came out. Is it the best time to go try it again before sun rise? And also what aperture should I set it at? I have an ND 8 filter should I use it? Any tips would be great

Isam,

Leaving the lens cap on, set f/64 or the highest you have, and at least a 30 min. Exposure, it may be a tad dark but just start adding to the exposure time until you get it to your liking

But seriously, is the camera digital? experiment with sunsets or sunrises ,use your ND
use high aperture all of these are ways to stretch out the exposure time.