Maintaining chisel angles when sharpening can be challenging but with a little practice excellent results can be achieved.
When sharpening chisels on whetstones it is very important to ensure that the stone is absolutely flat. We carry a range of whetstone flattening options. Remember that your flattening tools are almost as important as your whetstone when sharpening.
If you are having trouble finding the correct angle try colouring the bevel with a sharpie. Try and find the correct bevel and complete a few passes. Check the bevel and if the sharpie has been removed your angle is correct. If it has not then adjust the angle and repeat the process until your angle is correct.
To maintain the correct angle very carefully apply pressure to the sharpening edge and slightly touch the stone. This will help to keep good contact between the stone and the bevel.
Jigs and aides can help but nothing will improve your chisel sharpening more than patience and practice.