I would also suggest the Kiwi parade gloss that Che suggested, on that I would only use Kiwi polish, one reason it is very popular so if you are ever away and need polish you can get it anywhere and have consistency. But that is why I also suggest Kiwi polish; it is of very good quality and very consistent tin to tin.
Next is supplies, this is very important, you will need three brushes make sure that they are made of horse hair not nylon, some people use a cloth but I prefer a brush applicator, it is easier to get into the grooves between the sole and leather, so you will need a small brush applicator. I would also get a course brush, and then a soft fine brush; Kiwi does have the brushes as well. After you purchase them never use them for anything other than black, if you have other colors, get brushes for them.
Apply the polish all over the boots with the applicator, then let the boots sit for at least ten minutes, this gives the wax time to dry. Then with the course brush, give your boots a brisk brushing, this will remove the residue and your boots will begin to shine. Then with the fine brush, lightly brush the boots, this will polish the wax and you will start to see the difference. Then you can use a boot polish cloth to give it one more shine, but I prefer to use panty hose nylon, this will really bring out the wax, your wife or mother may not like this very much so ask if they have an old pair to give you.
Repeat the process till they come out the way you want, I agree with Franko and Che, do not try anything else like burning, or some of the liquid waxes, they bring out a quick shine but in the end get dull and you cannot get them to shine as good, never mind the cracking. And the more you polish them the shinier they will get.