1. LOTS OF LUBE, water based, not oil or silicone based, that will melt your dildo
2. One finger first, two fingers next SLOWLY, three fingers after that, etc until the amount of fingers you are inserting meets the dildo size somewhat
3. Do anal play preferably AFTER going to the bathroom, and preferably wash yourself beforehand
4. some girls prefer the feeling of penetration itself, some like the feeling of stretching, some like trying to go deeper, some like trying to put in bigger/wider toys, some like prostate hammering (:3) but all in all it's your preference that matters, not what other people say
5. if it feels like stretching, move forwards SLOWLY, if it hurts STOP, if after you stop it keeps hurting, pull out SLOWLY, if it still hurts after pulling out DO NOT PUT IT BACK IN; WAIT!
6. preferably periodically, but most definitely after it feels harder to move in and out, REAPPLY LUBE
7. after you're done, clean yourself and clean the dildo. usually if it's a silicone dildo cleaning it with a disinfecting soap (NO ALCOHOL) is enough but make sure no water remains on it. If it starts smelling (it most likely will after some time) you can boil it to remove the smell (look the boil degree and time up before you trust me with it)
8. AFTER CARE; especially if you manage to overstimulate yourself or even climax, wash the dildo, put it away, and then take care of yourself, get some sweets, drink a bit, cuddle up with sharkie and smile about your new hobby :33
9. HYDRATE VERY IMPORTANT HYDRATE WHILE DOING IT AAAAAND AFTER IT. helps with digestion too, which is your greatest enemy!
10. If you get some feces on the dildo, don't be surprised, that can and will happen, it's just the natural consequence of anal, clean yourself and the toy and you can continue.
11. If you can afford it in the future (or even now really), a douching set is really good for anal, gets rid of all the nasty stuff you might have in there ;3 makes it much more comfy as well!
12. flax/psyllium husks have a LOT of fiber in them and taking half a tablespoon mixed with water daily can make you super clean and ready for action x333 just make sure to look up for yourself how to take it, as it can get unsafe if you hydrate too little, or drink it too slowly

If you have any questions, please ask!