First off, you need to learn your basics, before casting any spell. Reading up on your basics is the best way. Because other wise you would probably get no where and not know what you are doing.
The basics are listed differently for everyone. But i have a list of the basics you can learn
The Basics are:
Meditation: You should really start out with meditation first, this will help you balance out all energies that you work with.
Visualization: While doing meditation or casting a spell it always important to have focus when casting. Always practice practice this.
Herbs/Tools: There are many different herbs and tools that witches use and don't use. For example some use herbs such as rose marry, bay leaves, lavender. Most of these herbs can use for protection spells. Now for tools, if you want to use any, there are such things as incense, oils/burners, candles. Candles can play important role, espically when they represent the witch and also colors.
Moon Phases: Learning the different type of moon phases is also important for spell casting or any ritual/spirtual work. There are waxing crescent which in this phase is to gain things such as money, luck, friendship, harmony etc. Wanning Crescent/Gibbous is to get rid of things such as negativity, evil spirits, etc and also good for cleansing a house or land or a even space or person.
Colors: If you want to use colors in spells such as candle colors, like yellow, blue, green, black, white. Make sure to choose which ones work best and for you. If you want to know more about colors just ask around.
Days of the Week: Now some spells or rituals can be done on certain days of the week or certain months. Some spells may not be able to be casted until on a Sunday or a Tuesday for example. Make sure to know what days to cast your spells on. Also time is important to remember.
Grounding/Centering: Grounding yourself everyday will help you loose any access energy you may have left over. So that way it dose not build up. Centering your self can help you keep focus and straight. Helps you concentrate on energy works such as energy manipulation or for example creating a psi ball. You should try to ground and center yourself everyday if you get the chance.
Short List of the Basics
Days of the Week
I hope this helps you.