Have someone learn the Machinist Specialty (Skills: Machinery, Operation) and max it out to LV10. Once you've reached Ionis, you'll be able to buy Mechanic's Toolboxes, which are consumable items for crafting using this specialty.
Keep crafting even if the character has no Design Sense Talent since almost all characters will unlock it as a Secret Talent except Ashlay. To increase your chances, it's better if you have the Orchestra Super Specialty unlocked or someone with Music and access to the Goddess' Arrival song.
One benefit of having this Specialty early is that you'll get access to Support Equipment that will help you boost your success rate for other Specialties and Super Specialties. So after crafting the at least one copy of the necessary support Equipment, you can sell the extra copies for around 150K+ fol each. Bump up the prices even higher by using the Group Appraisal Super Specialty.