I like a quickie glue pen or scrap happy glue because of the fine tip. I've also used glossy accents though I preferred matte accents which they no longer make because if I messed up, the mistake wasn't shiny. Sometimes I use a two way glue pen.
Joan from Joan's gardens recommends Ranger's Glue n Seal which to me seems a lot like matte accents. It comes in a small pot with a brush built in to the lid. You can brush it on the back and even if some gets on the front of the die cut, it dries clear and totally matte. So unless the paper you are using is glossy, it won't show. I don't prefer it but you guys might want to try it. I prefer to use it as a sealer.