Mortuary

My best friend died a week ago. I have been checking on her gf everyday and told her that I will help with whatever she needs. Today she asked me go with her tomorrow to do my best friend's hair. I agreed. All I have been wanting to do is see her anyway so it can finally be a reality an did course I want to be supportive. But it's like I want to be strong for her gf. I really don't know how this is gonna work because I have also never maneuvered a dead body. I don't know how I'm gonna react physically and emotionally. I had something like a panic attack after sitting and waiting for the plug to be pulled on my step mom. Does anyone have any advise? Like should I eat or go in on an empty stomach? Any advise would help. I hope it's really not that bad.