For you to be an MOT tester you will have to meet the DVSA criteria of eligibility and pass the A Level 3 pre- entry accreditation, have a level 2 award in the MOT testing certificate and have VT8 MOT test. All these tests must be DVSA recognized and monitored.
After you get qualified to be an MOT tester you will be supposed to undertake the MOT annual training, pass an assessment and be able to retain your status as an MOT tester.