How to Lighten the Color of this Darkened Louis Vuitton Vachetta Leather Handle?

http://i300.photobucket.com/albums/n...e-Vachetta.jpg

Picture 1854:
Handles with treated and untreated.
Please advise how to do lightening the color of the darkened leather
- do I have to put the solution on a clean rug and wipe directly the leather? or dab the solution in a sponge and rub it in the leather ?,
or dab the solution in the leather directly and let it dry?
I will appreciate your advise on how to proceed.
Thanks