Spells are always best if you make up your own as you can charge it better with your own energy and intention. For me, a yellow candle works best (others may have different suggestions but colour can also vary by what category of good luck you are looking at....eg money - green, health - blue etc). You can also do a spell to banish bad luck (as moon is waning now).
You can decorate your altar with things that represent good luck (wallet, money, keys whatever has meaning to you). If you are familiar with runes, you can carve a relevant one into the candle together with an inscription of what you want come your way.
Cast your circle and carry out your spell, letting your candle burn out or for as long as possible (you can complete the burning another day) but if you are putting out the candle, don't blow it out and try not to share what you're doing with too many people unless those people are going to help you. Magic works best without interference unless intentions are positive.