To certify a high school transcript for your homeschool student, sign and date the bottom section. As the instructor or principal for your homeschool you have the authority to certify your child's transcript.
Occasionally a college may request that the transcript be notarized. In this situation, leave the bottom of the transcript blank until you are in the presence of the notary. They will witness you signing the transcript and they will then sign and stamp below your signature to notarize it.