Summary

“Some people say nothing hits the G-spot quite like a nice hand in the anus.

Well, that might be true so let’s go through some rules for a safer
F - I - S - T - I - N - G.

Rule number one: Communicate.
Partners should thoroughly discuss each other's limits, experiences and skill levels, making sure everyone is consenting and comfortable. Communication must continue throughout the sexual act.

Rule number two: Stretch it.
You will want to feel comfortable with the feeling of stretching your anal sphincter. You can start small (finger, small and smooth butt plug, etc.). Make sure you slowly pull it in and out.

Rule number three: Lube up.
There can never be enough lube for anal penetration no matter what insertables you are using so always make sure there is enough. Note that there are special lubes for fisting.
Starting slowly and with lube will help you avoid some damage, such as anal fissures.

Rule number four: Wear gloves:
Gloves will block fluid contact, and protect the body from germs. Gloves can be made of latex or nitrile for example. Even with gloves, make sure to wash your hands and arms and cut your nails. No one wants to feel fingernails in their anus.

Rule number five: Enjoy.
Enjoy means a lot of things such as: taking breaks, knowing your limits, avoiding comparing yourself to porn actors, and accepting the fact that it might not work the first time. It’s all about pleasure, kinkiness, and of course safe sex.

Now go have fun ;-)”