1, you can spray the chassis armor first (divide the lines with paper tape first, seal the upper part without spraying glue with newspaper and paper tape, and then spray the chassis armor. Tear off the newspaper and paper tape when the chassis armor is not completely dry)

2. After the chassis armor is dried, spray the threshold primary color paint primer and topcoat.

3. After the topcoat is dried, it can present the effect of hammer paint on the factory threshold.

I hope I can give you a reference.