Do this is sacred space if possible - this can be as elaborate as a full ritual Circle, or as simple as a quick meditation where you visualise yourself in a protective sphere of white light (or whatever colour you chose), and ask for the Goddess to be present.
If you wish to set the candle up but burn it at some other time, then this can be done at any time. However, if you want to set the candle up and burn it that day/night, do it when the moon is WAXING - i.e. any of the fourteen days up to and including the full moon.
You will need a white candle, the words you wish to use, a black marker pen with a nice pointy end. Also some anointing oil if you desire. (eg. Your favorite essential oil).
The words are written onto the candle, start at the top and twist it round and round and round and round as you write. It is a bit tedious, but this way you become very focused and have to put a fair bit of energy into it. You can anoint the candle with oil afterwards, and although it does smudge all the words, the point is you have infused it with your energy - and whether the words are visible at the end or not does not really matter.
The words which are following are a general guideline and they can be changed to suit your needs. Just always keep in mind that any spell should be sent in love and with the good of all in mind. This is because any spell is energy that is sent out into the Universe. This energy does much travelling, and in doing so it will move through people, buildings, animals, plants, earth etc etc. Sending it with love and the good of all in mind will protect these things from any effects the energy may have, and could even help some people/animals/plants etc along the way!
O.k., here it is: (and it does fit on a full length tapered candle if you write small enough):
I, (your name), with the blessings of the Goddess and God do send this
out.
With the love and wellbeing of all I do send this out.
With the Sacred & Ancient Seal of Protection I do send this out. *[Draw
an Ankh, or any other symbol you feel fits such a description].*
Ye Mighty Gods I do petition.
May I be protected from harm
May blessings pour forth upon my family, my friends.
May blessing pour forth upon me.
Ye Mighty Gods I do petition.
For a life companion I desire.
One who is true of heart, caring, honest, gentlemanly,
Loving, warm, humorous. *[put any other attributes you would like]*
Who loves me for all I have to offer
And for all whom I am
And for one whom I will love for all he has to offer,
And for all whom he is.
Ye Mighty Ancient Ones
I do Petition.
So Mote It Be!
*[Now draw a pentagram, a pentacle and an Ankh, or any other symbol/s which you relate to. I did these three while thinking "May the powers of the Five Elements and Our Blessed Mother Earth Seal and Bind this spell, and May the Power of the Ancient Symbol for Life Protect this Spell.". So you can seal it with whatever power you can think of or you believe in.]*
Then hold the candle in between the palms of your hands and imagine energy flowing into it. Sometime you will feel a really nice warm feeling flowing into the candle. Visualise the outcome of this spell. When you think you have done enough, then you may annoint it with oil*, or just light it and let it burn until it goes out of its own accord, or wrap it up in some white tissue paper until you are ready to burn it.
It might be a good idea to have a time limit in mind when you do this, for example, you would like this to happen within the next six or twelve months. That way the spell can time itself to some degree. If you leave no time limit, then it might decide in five years time that it will work!!! It is up to you, but a time limit is generally recommended!
As I said this spell can be altered in anyway (but try to make sure you do leave that reference about harming no one in the process.). You can use this method for doing healing, bringing luck, prosperity, a job, etc etc. A white candle is suitable for any spell, as it embodies all the colours of the spectrum. However, if for example you think blue is a really good healing colour, then use a blue candle for healing! If you think green is a good colour for prosperity or fertility, then use green candle for such spells. If you aren't sure what to relate to which colour, then go with the white.