Answer (originally posted by @Nick V. owner of one B Nelson, one of the most renown shoe repair shops in the USA): Not easy for a laymen to do but, if you are going to try it, it will take some patience.
Find a crayon as close as possible to the color of your boot.
Soften it with some heat.
Fill in the area.
Let it set.
With the back of a spoon, gently rub out the area until there is no wax causing any seams around the area.
You will see a difference in color. That's normal.
Use masking tape to tape the top of the welt. What you are doing is protecting the welt and white stitching for the next process.
Get some leather spray as close as possible to the color of your boot.
Lightly (and I stress LIGHTLY) mist the area to blend in. You should do the same thing on the toe of the other boot to match.
Let it set until completely dry.
Lightly apply a coat of conditioner.
This Q&A was first posted in our Official Shoe Care Thread.
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