Our tannery has used Danner Boot Dressing (clear) with positive results. Smith's All Natural Boot Balm is also very popular among our employees and is Maine-made. However, there are many other companies that sell very similar boot dressings. We do not specifically recommend one brand over another.
For any new dressing, we recommend testing a small patch of the leather to make sure the results and darkened color are to your liking.
5-Step Cleaning/Dressing Directions:
1) Use a damp towel to wipe any dirt off the boot.
2) Once there is no noticeable dirt on the leather, let the boots dry fully.
3) Take a clean, dry towel and apply a liberal coating of clear boot dressing to all leather. It's normal for the dressing to sit on the surface. You will probably want to repeat this step 1 or 2 times to make sure every bit of leather is properly coated. The leather will absorb the dressing slowly.
4) Let your boots sit overnight so the dressing can work its way into the leather. You will typically want to let them sit for close to 12 hours. If you want to drive the boot dressing in quickly, you may apply heat (directly with a blow dryer or indirectly by placing the boots near a stove or other heat source), but doing so will immediately darken the boots. We do not necessarily recommend this approach unless that's the look you want to achieve.
5) In the morning, there might still be some boot dressing on the surface of the leather. Wipe off the excess with a rag, and your boots should be good to go!
Note: The more regularly you dress your boots, the darker the leather will become over time.
Feel free to check out the following video for some further information/instructions: Leather-care Guide