Well, blood magic only requires one or two drops of blood, and it should only be used with extreme caution. Basically, a safe way to do it is use a sterilized needle and pin prick your finger and only use one or two drops. You shouldn't make yourself bleed excessively for it. And yes, it will enhance your spells, since blood is essentially our life force. You can add the drops into an essential oil and use it to dress a candle if you do candle magic. But afterwards you should thoroughly clean and dress the wound, and dispose of anything that your blood touched.but as I mentioned, you should be extremely careful so you don't hurt yourself too bad, or get the wound infected. And if you do choose to use blood magic, you should never put your blood on someone else, or drink or consume it in anyway since even like a tablespoon can cause haemochromatosis.