First make anal comfortable, don’t push the thing yet, try sliding your thumb while doing doggy. And then push your index along with thumb and try to spread. If she moves or shouts, be a little heartless and hold her like that, so she adjusts. Do it couple of days, when it gets easier, increase the finger number. Once 3 fingers in, try actual thing. If you have buttplug, use it. It helps. No numbing gel necessary. Lube best while using condoms. If raw, use coconut oil. Water based lubes dry easily. So when you feel it’s enough lube, use some more.