Couple things I can think of:
(1) Turn in Poetics for Soils to sell on mb
(2) Turn in Creation for NQ mats to sell on mb
(3) Gathering is the best option to go from no gil to having gil all it takes is a little time. Check your mb to see what is worth your time to gather at that particular time
(4) Crafting can make you a lot of gil, however, to maximize profits you should gather everything yourself. The only exception to this would be if it is extremely time consuming and there is a cheap alternative like having a component you can buy from a vendor
(5) Hunts. Save all cracked clusters until materia vi prices hit a high point then dump your stock onto the mb. If you have a lot then diversify across multiple materia types. If you dump too many onto one type you will crash the price and won't make any money.
