Sanding small and "tiny" is always a pain. I started with fingernail files and emery boards, not good enough. Decided to make my own sanding boards, in various shapes and with graduating grits.
Use nice flat smooth boards or hardwood dowels sized to what you will need for the job. Cut the sand paper nice and square, using thin CA lay the paper backside up and glue a wide side first. Then run a bead of glue a tightly fold over the board. Allow each section enough time to set before doing the next or the paper will peel up at the edges later.
More "HOW i DID IT"s, later.
I'm going to get this going soon. Problem is that I spend most of my time out in the shop and the comp. I have out there has most of its horsepower tied up with my 3D engineering/modeling program. Makes it real slow doing anything else. Have come in the house to use the wife's computer. But I'll get all the "how I did it" posted soon, need more step by step photos yet also. Mike.