With tiny brush allows better access to more difficult areas such as the welt (all around), all the rest (leather) you can opt for a lint-free tissue to wax all the leather.
The wax can be used either on the leather or the welt around.
After the application of the wax should be allowed to dry about 5 minutes and then pull the polishing with the aid of larger brush. This brushing should be shallow (no pressure) and fast so that the brightness highlight.
Still another possibility is to merge with the wax also water (just a few drops) and applied all over the shoe without rinsing, leaving no water balls during dry. The water and the wax will enable higher brightness yet.