Covering a tattoo also needs its own covering.
Thats right, covering a tattoo to make it look like it doesn’t exist is only part of the “battle”. The next task is to seal the tattoo covering in order to protect it from the elements. What are the elements? This could be anything in immediate contact with the makeup covering such as clothing or elements like chairs or jewelry. Other situations could be more climate based, rain, heat, water (like pools or the ocean). Is the person or actor going to be active, creating sweat or aggressively grappling with someone for instance a fight sequence with stuntmen. The truth is, it could be all of this rolled into one. This is why covering the cover up is so important to consider.
First you must consider what you are covering the tattoo with to begin. This will almost definitely dictate what you will seal that cover makeup with.