Pick the design or drawing of your choice.

Convert the drawing in Vectorial with the function “trace image” and select engrave.

This will give you the chance to use slightly different settings and speed.

Make sure of centring the graphic exactly in the middle of the hip flask.

Don't need for a jig if you mark an X on a paper and place it on the base of your laser.

Fire it up with the settings given in the screenshot.

Use the IR laser at an higher speed for a neat clean up.

Wipe it with a dump cloth to remove any residual dust. And the artwork is completed.
Rubber can be a fussy material, try to avoid any spry, soap or bleach product. If you wallowed the steps above, warm water will do just fine.