I don't cast spells for anyone i don't know personally! I'm 50 years old, straight male, and i practice Witchcraft as an art, and take it very seriously, it is nothing to play around with. I practice alone and follow no single set religion, path, or tradition, i utilize portions of many into my practice. I do not believe or follow any law of three (three-fold law, law of return).
I am a Solitary Eclectic Witch (simply put, an eclectic witch is an individual approach in which the witch picks and chooses from many different traditions and creates a personalized form of witchcraft that meets their individual needs and abilities. They don't follow a particular spiritual path, religion or tradition, but study and learn from many different systems and use what works best for them). It's sort of like what Bruce Lee did with martial arts, he didn't follow a set style, he utilized portions of many different styles, and created his own. I cast many types of spells that i create on my own as it fits the situation at hand.
Do your research, study and learn how magick works from reliable sources, learn to write and perform your spells yourself, your own energy going into a spell, will be far more effective than relying on someone else to cast it for you, they will not know your intentions better than you. We all contain energy within us, and we all have the ability to use the energy of the universe that surrounds us. The trick is to harness and direct that energy. By focusing your thoughts and actions during a spell, you can learn to do that. Visualization/visual imagery and rhyming words in spells, help many to tap into the right-side of your brain that handles all creative thought, The rhyming isn't totally necessary, but for many it just sounds better, and that can help you memorize the spell you write much easier.
In addition, although not totally necessary, you can further fine-tune your desires by adding all of the "extras" or tools that go into a spell (candles, stones, colors, herbs etc.) Each of these items has its own form of energy that you are bringing into the mix, overall the most important tool in witchcraft is the mind, it's all about your intention, so if the "extras" or tools mentioned above help create that intention and energy building, then utilize them.
Same goes for moon phases, utilizing moon phases into your spells for certain situations, full, waning, waxing, new/dark, is another way for energy building, again it is not totally necessary, but if it makes you feel good, and it helps you in your mind for energy building, and stronger intention, then utilize it.
When you set your pure intentions and declare IT IS DONE! with zero doubts, you implant your intention into the Universal Matrix, summon the power that creates worlds and declare it into physical reality, this is a very powerful practice!