Makes mistakes
• Blunders
• Bobbles
• Boo-boos
• Bungles, with up
• Errata
• Foul ups
• Loafs, with off
• Makes a boo-boo
• Makes a minor mistake
• Messes up
• Mishaps
• Mistakes
• Screws up
• Screwups
• Slips
• Wastes time (with off)