step1, If you buy only one gem item in this game it should be Banker's Guild (no this does not replace or require you to leave your current guild)
step2, Protection Charm
step3, Time Capsule
step4, Premium Ally (ask in chat which one is best atm)
step5, Cap of Wisdom
step6, spend gems on LP for stat increases
step7, only after the cost to increase stats by 3 with LP cost more gems than the boost items you will want to buy: Hermes' Boots, Hercule's Guantlets, or Royal Crown.
Note: Skill Capsule and Invisible Cloak are not recommended for purchase and Hercule's Guantlets are only recommended for sword users