Farm crystals and hope they sell? or is there a better way to make some gil
Yes, there is a better way, use those crystals to craft with!!
Peeps will say that "crafting is expensive" - forgive them for they know not what they speak of. Mostly they are repeating what they've been told. In low level crafting the most expensive item tends to be the crystal. Instead of selling your crystals for next to nothing, use them to craft stuff to use and to sell for more profit than you'd get from selling the crystals. Start thinking about crafting with the question: what can I do with these crystals?
Obviously crafters will buy your crystals from the AH because they use them to make gil.
Below are suggestions for what you can craft with your crystals. As you craft things, you'll get "skill-ups" in that craft (you'll receive a message saying: "Your goldsmithing skill increase 0.1") Below I've noted the level where the synthesis stops giving you skill-ups (note - you'll only receive skill-ups occasionally, don't expect them every synth). Try not to synthesize something that caps more than 5 levels from your current level. Once you've reached the level cap for the item, either move on to a harder synthesis, or choose that synthesis only for profit-making.
You'll need to camp your AH to see what items are selling for in San d'Oria on your server. There is no way for me to tell which of the below synths sell for a profit on your server. Don't be afraid to list things for more than the AH history shows. Peeps have a bad habit of selling things at the same price as previous sales . . . and many of these sales prices are driven by power-levelers who are crafting in huge volumes and sell for a loss on the AH. My advice is don't do it that way. If someone is monopolizing the sales and selling at prices that reflect a loss - don't craft that thing. Make something else. Before long that power-leveler will cap that synth and move on to ruin other markets (to finally reach 100 and cry that "crafting is expensive" because that's the way they did it).
You can get many of the items below from fighting things (worms drop flint stones, hares drop hare meat, etc.) On the left of this page you'll see a "Search" box - this is your friend. When you see an item like "wijnruit" which you need to make antidotes, just plug that into the search box, and you see where you can score that item.
Consider for a moment what you can do with fire crystals. My recommendation is to first make a stack of copper ingots. Copper ingot is fire crystal plus 4 copper ore. Get your copper ore from the Smithing Guild in Norther San d'Oria. Copper ore will cost around 9 gil per ore, 36 gil per ingot. So a stack of copper ore will cost you a stack of fire crystals and 432 gil in ore. You should get around 4k for a stack of copper ore. So you will make around 300% profit. However, don't expect to be able to sell an infinite number of stacks of copper ore. Get a feel for how many the market demands.
What follows has an emphasis on what's available in San d'Oria. Here are some of the items you can craft with zero skill in crafting: Wind crystals
: Stone arrowheads
- wind + 2 flint stones = 6 stone arrowheads (goldsmithing-2) Arrowwood lumber
- wind + arrowwood log (woodworking-2) Chocobo fletching
- wind + 2 chocobo feathers (clothcraft-2) Luan lumber
- wind + luan log (woodworking-3) Wooden arrows
- wind + arrowwood lumber + flint stone + 2 chocobo feathers (woodworking-4) Peeled crayfish
- wind + crayfish (cooking-3) (Peeled crayfish is bait for fishing. Using this bait, you can fish up "items" in easy areas with this bait, but see if you can sell on AH for profit. You can fish up tons of crayfish.) leather bandana
- wind + sheep leather (leathercraft-5) Earth crystals: Stone arrows
- earth + arrowwood lumber + chocobo fletching + stone arrowhead (woodworking-3) Notice that you can craft all of these ingredients! Vagabond gloves
- earth + cotton cloth + sheep leather X 2 (leathercraft-3) Vagabond boots
- earth + bronze scales + grass cloth + sheep leather X 2 (leathercraft-5) Bronze cap
- earth + bronze sheet + sheep leather X 2 (smithing-4) Bronze mittens
- earth + bronze sheet + sheep leather (smithing-5) Cesti
- earth + ash lumber + sheep leather X 2 (leathercraft-3) Water crystals: Antidote
- water + San d'Orian Grape + wijnruit (alchemy-3) Honeyed Egg
- water + bird egg + honey (cooking-3) Fire crystals: Copper ingot
- fire + 4 copper ore (goldsmithing-3) this is a nice synth for beginners because there is no HQ - high level and low level crafters have a level playing field Bronze ingot
- fire + 3 copper ore + tin ore (smithing-2) Bronze dagger
- fire + bronze ingot + copper ingot (smithing-3) Roasted corn
- fire + millioncorn (cooking-2) (only if Sandy controls the Aragoneau Region; then see Antonian at J-8 Northern San d'Oria) Sweet Lizard
- fire + lizard tail + honey (cooking-3) Pebble soup
- fire + distilled water + flint stones X 3 (cooking-5) Grilled hare
- fire + hare meat + dried marjoram (cooking-6) score the dried marjoram for @ 43 gil from either Benaige F-7 Southern San d'Oria or Phamelise K-9 Southern San d'Oria (neither NPC has this stocked all the time) Dark crystals: Sheep leather
- dark + sheepskin + distilled water + windurstian tea leaves (rarely available from NPC in Sandy, check Auction House) (or use willow log in place of tea leaves) (leathercraft-2) This is a key synth for leathercraft, smithing and bonecraft -- make tons of these, sell some for profit and keep the rest for crafting.
Crafting is 'da bomb! Enjoy.