LB -
You have several options -
1 - Gently wetsand your final colorcoat with a 2000 grit wet/dry paper (the key word here being GENTLY, you don't want to sand paint off of edges or corners), or 000 Steel Wool. All you want to do is give yourself a good base for Clear Coating. You can Clear coat with Future, either spray with an airbrush, or brush it on if you do not have an airbrush. Future is nice in that it will even itself out leaving a minimum of brush strokes. Let dry completely without touching. You may alternatively choose to airbrush an enamel clear coat (or lacquer, depending upon what kind of paint you're using for your color coat), but IMHO most people are now going the Future route.
2 - Shoot or brush the Future without presanding the topcoat - not as nice a look as the Future will not "fix" any body imperfections you may have from your final color coat. The upside is that you won't have to worry about possibly oversanding an area prior to clear coating.
3 - I haven't tried this, but I have heard of people using Pledge Furniture polish to wipe down their models after the final top coat to give a more glossy finish.
4 - If you clear coat or not, you may also get some polishing compound from WallyWorld or someplace similar, and gently polish the model. You could also wax the body with a good car wax .
Whatever method you finally decide on, take your time and don't be in a rush. If you take the proper amount of care, you should end up with a really nice finish. Give it a try, and post pics when you're done.
HTH
lowdog