Use the Kölbli/Sassheimer extraction, it is fast, easy and almost impossible to fuck up and always worked great for me.
Take 100 gr of the ergotamine (tartrate) and mix it with 556 ml of normal milk (pasteurized, homogenised OK) 3,5 % fat. heat the milk for about 3 min to 76 C.Let cool to 37 C.
Then add 156 g Roquefort cheese and mix in a blender for a minute.
Fill in a big jar or devide in some litle jares and let sit on a heating device at for about 7 days at 27 -33 C and watch the ergot crystalls develop as a crystal foam on top of the jar.
The foam is pure ergotamine. It can be cropped and used, or stored in a freezer. Let the jars sit, until no foames are developed anymore. You can then eat the special roquefore, it contains no alkaloids anymore.
Dont get annoyed by the smell, it is normal and may be fixed if you place a sardina in the jar, but the yield will be little less.