First of: Yeah I am aware that most likely like 80% of you people already know this, this is for the remaining 20% who dont know:
Bandages sell to NPCs for a higher price than the cloth you need to create them from Silk upwards.
Example Runecloth sells for 4 Silver a piece to Vendors. Runecloth Bandages sell for 5 Silver.
2 Runecloth sell for 8 Silver, 1 Heavy Runecloth Bandage sells for 1 gold.
So, even if you are a class with self heal, just pick up First Aid for some sweet money^^
Silk Bandage instead of Silk Cloth: +10 Silver per Stack
Heavy Silk Bandage instead of Silk Cloth +20 Silver per Stack
Mageweave Bandage instead of Mageweave Cloth: +30 Silver per stack
Heavy Mageweave Bandage instead of Mageweave Cloth: +20 Silver per Stack
Runecloth Bandage instead of Runecloth: +20 Silver per Stack
Heavy Runecloth Bandage instead of Runecloth: +40 Silver per Stack