More often than not, I dye onto dampened leather, as this stops the leather from sucking up too much dye when you first place the dauber onto the leather. Also, keep the dauber moving - otherwise you are likely to get patchy results.
I'd also suggest that you may want to dilute the dye before application. When I started, every dye that I applied came out dark brown (even the light brown ones!). If you are applying diluted dye, it probably doesn't matter too much about dampening. I dilute the oil dyes with industrial meths (99%) but surgical spirit (95%) should also work.
If you have any bits of scrap, (even just a square inch or so) I'd suggest a bit of practice onto that before you go for your main project.
Remember also, that applying a finish (e.g. carnauba wax) will usually darken the colour.
Another good applicator is made from cut up Ugg boots. The sheepskin lining is good for applying and spreading the dye.
Also, with leather being a natural material, you won't (in my experience) get a perfectly even coating.
Geoff
