What can you all tell me about making my own candles at home on a budget?

I was given some AMAZING fragrances by a friend. I do not wear such things but I love to fragrance my room with them.

I am thinking of making candles with the “imps” and would love some information on how it can be done on a budget.

Can anyone give me pointers? What is the best kind of wick? I would rather put my meager funds into the wicks and wax if possible.

Also- what kind of wax? What is this about wax additives? (Aside of scent and color)

Can I use a double boiler and a candy thermometer?

Please lend me a hand here Jellies. Many thanks!