What supplies do I need, or do I even need any?
Are my supplies relevant to the spell?
Could this spell backfire on myself or others badly?
Am I able to cast this spell in a way that is effective?
Do I have the correct mind at the moment to cast this spell?
Do I really 'feel' this spell?
Do I have strong will towards this spell, whether good or bad?
Supplies are things that could possibly help make your spell more potent; however not all people use them. Some just find it easier to simply say the spell without any supplies such as incense, candles, a wand, etc. This is intirely down to the caster; and their intuition if they need anything.
If you do choose to have supplies, make sure they are relevant to your spell. For example, it would be quite unusual to buy a bright orange candle for a money spell. (Money spells are usually associated with the colour green.) However, if in your opinion you think the colour pink has connections to money, you could use a pink candle. It is all down to your opinion, and what links you as a person make.
2. Will in a Spell
You noticed I included in my questions ''Do I have strong will towards this spell?'' or something similar. This is because, in my personal belief, the more you want something, the more it is likely to happen because of the way you strive for it, out of pure emotion. It is more likely a spell you dont really have your full will behind will not be as effective.
For example, magick has no colour. Yet we brand it with labels such as 'black' and 'white' to help with easy association. But of course, it depends on one's views. What one may view as 'black' magick, another person may not see as 'black' magick.
Revenge spells would be a good example of this. Some people say they are good because they get revenge if somebody has done wrong, but other people may say revenge spells are morally wrong, because they believe that two wrongs do not make a right; and if they believe in karma, karma will 'bite' that person back.