How would you create a high gloss finish on furniture?
If your existing finish truly is lacquer, all you would need to do is apply additional coat(s) of high gloss clear lacquer.

Always use the very best brush you can afford, or spray it. Lay the material flat, for best results. If you have no experience with this type of finish or with the application techniques mentioned, you should practice practice practice on some sample pieces first (and read a book about working with lacquer, maybe).