Because you have left the wax resist to sit while drawing on your design, any particles of colorant that hadn't been completely soaked beforehand should have become so at this point. If a skin should have developed over the top of the resist, discord it. Stir the wax resist again, just prior to use.
Choose your waxing tool with an eye to the kind of line you are looking for. I wanted a fairly well-controlled line so chose to use a toothpick rather than a brush. For truly controlled and even fine lines (suitable for use only with a very stiff glaze), you can use tjanting tools... a specialized type of tool used in batik to apply hot wax to fabric. If you are interested in tjanting tools, do be aware they come in various sizes depending on line thickness desired.
Apply the wax carefully to your drawn design. I applied thicker lines than were drawn, since I knew I would be using rather fluid glazes and didn't want the design accidentally eradicated.
Once the colored wax has hardened, you can apply glaze to the pot. I poured the interior glaze in then out, and used a brush to apply the three different glazes I used on the exterior.
Be sure to clean any excess glaze from waxed areas, as the glaze might fuse to the pot during firing, or worse, drop off and melt on the kiln shelf.