Small back scab forming?

I got this tattoo done on my leg early January this year, and the healing process went great, in the last week or so I noticed this small black scab formed over the top of the tattoo, what shall I do?

I got this tattoo done on my leg early January this year, and the healing process went great, in the last week or so I noticed this small black scab formed over the top of the tattoo, what shall I do?