Family Handyman - DIY Tip of the Day: Chisel sharpening basics. To hone a chisel with an undamaged edge, first polish the back by rubbing it back and forth on wet/dry sandpaper
How to Sharpen a Chisel (DIY)
How to Sharpen Your Woodworking Tools With Sandpaper : 9 Steps - Instructables
How to Sharpen Your Woodworking Tools With Sandpaper : 9 Steps - Instructables