I've had good results with this procedure, which someone on this forum provided but I've forgotten who:
- Cool beer to 32-33ºF let rest a day or two (ideally in the fermenter).
- Prepare gelatin: 1-2 tsp dissolved in 1 cup of water.
- Let rest 30-45 minutes; you should not see any gelatin granules anymore.
- Heat in microwave until mixture gets to 170ºF.
- Stir just until everything is homogeneous.
- Add to beer, stir gently, and do not disturb trub at the bottom.
- Pull sample 2-3 days later to confirm clarity, rack to keg, carbonate.