Be positive. Be Honest. Be of Pure intent.
Negative energies will always block your spells. So it is vital to spells and rituals to have reasonably selfless goals.
Words have power. Sound has power. Rhythm is a wonderful way to focus your thoughts and strengthen your spells, which is why so many poems can be used as spells. For example the long version of the Wiccan Rede as written by Gardner's priestess Doreen Valiente. However you do not need to be poet to create Wiccan spells. Basic incantations like "Goddess Bless and Goddess Be, for all you've given I thank thee, will help you to center yourself as your prepare your spell. Try reciting a simple incantation like one above to yourself in sets of three. Three sets of three has a very natural balance.
Focus on your thoughts and your breathing as your recite your incantation. You may choose to say your incantation aloud but you may prefer to simply recite your chosen incantation in your mind. However, you feel most comfortable is the best way.
Remember: Negative energies will always block your spells.
