My first time using varnish on a Gundam: suggestions?

I’ve never varnished a model before. But I used water slides on this RG Tallgeese, and I wanted to seal them.

My local hobby shop only had gloss varnish (Vallejo), so I went with that. I’d heard that matte is better at hiding the edges of decals, but this is what’s on offer.

I do like the shiny look on this Gundam (or proto-Gundam, ur-Gundam), it matches the pilot’s personality. But I would like to try matte in the future.

Any suggestions to improve my varnishing for next time? Advice most welcome.