For relief engraving wood, we recommend using the following process (based on using a Speedy 360, 80W laser): Engrave your image in 3-4 passes with high power and low speed (p=100%, v=30%) to make your engraving the depth you want. Then, we recommend one or two rounds with low power and high speed (p=60%, v=100%) to remove any smoke residue.
If you want an extremely deep engraving, we recommend you first engrave the cutting contour then only do the deep engraving.
Clean your relief engraving with a toothbrush and soapy water or detergent. Liberally brush over the relief and scrub away any traces of powder. However, be sure not to use too much water and dry your workpiece well, for example by using a method like compressed air. Otherwise, the piece of wood could lose its original shape.