1. It should be safe.

2. You must be able to get privacy at some point in your magical place.

3. You need enough room to be comfortable and move around.

Your first step will be to begin surveying your choices of spots. Some people may instantly know where their magical place is.

But if you are not one of those people, I will tell you how to find, bless, and utilize your magical place.

Write down a list of places which are nearby enough to visit often that you like and that fulfill the three requirements for a magical place.

Visit each place and meditate there for awhile, absorbing the energies of your surroundings. Contemplate whether you would feel truly comfortable working here. You should feel a sense of security and freedom.

Once you find your place, you should begin to prepare it for magic. You'll need a place to store magical supplies. If your spot is indoors, this is easy.

 A box under a bed or in a closet will serve nicely as a supply keeper. You can easily arrange jars and bags of herbs, stones, books, candles and other useful items in your box and even decorate it to give it more personality.

If your place is outdoors, the drawback is that storage may be a little more difficult.

Here is my solution, though you are free to think up your own work around, Purchase a plastic Tupperware container large enough for your items that you need at hand.

Dig a hole near your magical place deep and wide enough to set the container in.

Fill in the area around it and put the lid on top of the container. Now, conceal the lid - this can be done with a layer of soil, sod, or even a potted plant as long as you can easily move the conceal mean to reach your items.

If you have stepping stones near your magical area, you could just place a large, flat stepping stone over the storage space instead of using the lid.

If this method is impossible, you can keep items inside your house and carry them out whenever you need to use them.

It is just more convenient to have your storage space handy.

Things you might keep in your storage space:

Candles 

Candle holders (for safety) 

Incense sticks or cones 

Empty dish 

Jars or bags of herbs 

Written magic, books, and/or a Book of Shadows 

Stones and/or crystals

These items will be readily at hand when you need them

Next, it's time to cleanse away any negative energies in your magical area. Light a white candle and cast your circle.

Take a broom or besom and sweep the area, imagining cleansing, white light flowing from your hands down through the handle and out onto the floor.

When you feel that the negative energies have been "swept" away, sprinkle salt around the area.

Optionally, you may light a stick of sandlewood incense.

Home sweet home.

You should use your magical place in magical workings as much as possible. You should also meditate and pray in your space whenever you can.

It is your sanctuary.