I use mine for various things. If I have a lot I use it to upgrade buildings and/or knowledge. To ME thats priority one, two and three. Otherwise I use them for speedups. Those are versatile as they can be used for buildings/knowledge or speeding up troop training. I WOULD NOT use Gold for troops as the speedups are both cheaper to use and will cost way less than if you just paid for the troops.
Gold can be hard to get , depending on your Clan and ability to buy Gold. ONLY get the packages when/if you spend real money. The "extra" Gold is way cheaper that way, buying Gold from the bank is wasteful.
Always try to have plenty of Peace shields and re-locations too.As a newer player, as I take it you are, the Peace shields are probably more needed.
Try to get as many achievements as fast as you can both those you can see and the "hidden ones" as for some of them the Gold is quite substantial. Ask your Clan mates for a list of the hidden ones as the older players SHOULD have them.