If you're looking for clemency instead of a loan, head over and check out the etters for misbehavior, social slights, workplace issues and personal apologies. The new forms can help atone for troublesome or delinquent behavior at work, school or in the community. These include apologies for graffiti, interruptions, tardiness, and violent behavior. I advise using these as launch points to give you ideas for more personal, specific apologies.
You can learn to design printables with free options like Canva, or Paint. These programs are fine for basic designs, but can be very limiting. If you would like completely custom designs, programs like Adobe Photoshop and Illustrator are excellent.