Get an airtight bag from a medical supply store, they usually come with catheters and tubing but you might have to buy those separately I don’t know. Just hook yourself up to that and the bag will fill up and you can just connect another bag to the tube when it’s full (MAKE SURE NOT TO GET ANY AIR IN THERE, IT WILL CLOT, EEEW).

You can cut yourself if you want to but you’re better off saving razors for shaving and blood for bagging. Generally if you take more than 2 bags of blood given the bags are standard size, you will die. I feel as if I have a responsibility to tell you that, but forgetting it is fine.

When you’re done mail the bags to me in a thermo-regulatory envelope. The people at the post office will look at you funny, that’s how you’ll know you got the right kind of envelope.

In case you do take more than 2 bags of blood it might be a good idea to write a note and my address on the bags before you start because I really do need it.