When I want to work with luck, I use orange oil. I may anoint a candle with orange oil and speak my desire into the flame or I may dilute the oil and wear it as a fragrance in a situation where I need an extra bit of luck.
For prosperity and wealth I like to use basil oil or almond oil. The colour green is associated with wealth and money so anointing a green candle with basil oil while focusing on a visualisation of your finances improving (maybe visualise your bank balance showing a positive figure) will have a beneficial affect on your personal financial situation.
Blending luck and wealth spells together may bring you a little windfall. Try using a orange candle dressed with almond oil and a green candle dressed with orange oil. Speak your desire for more money into the flames. (Rhyming optional, quite a Wiccan thing but I do find if I take the time to write something that rhymes it means I have spent more time on it and therefore more of my intent goes into the magic.But if you can't rhyme, don't worry, it is your intent and concentration that is the important thing here.)
I recently made my husband a blend of basil and orange oil to wear at a job interview and I am pleased to say that he got the job.
A word of caution about luck spells. Magic works in conjunction with your own intent and your own will. Part of this is demonstrating the effort you put into a situation beyond the magic. Taking the job interview as an example, I would never recommend you do a spell and then sit back expecting the spell to do all the work for you. If you don't prepare, practise and turn up looking smart, all the magic in the world won't make a difference. There is a lot of truth in the maxim that we make our own luck.
That said, good luck!!
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