Have iPhone Replacement but Cannot Turn my Current iPhone Off

I received my replacement iPhone X in the mail yesterday. I went to follow the instructions I was given with it for the process of returning my current (damaged) iPhone X in exchange for the replacement. The 4th step is to shut down/power off my iPhone, however the damage to my current phone does not allow me to slide to shut down/power off. I got the assistive touch button, but that only allows me to restart my iPhone. What should I do? Is there another way to accomplish this? Is it okay if I don't shut the phone down before removing my SIM card?