I say just watch the baby! Because its your sisters child!
IM ALWAYS NERVOUS before!!
But then after im babysitting everything is good!! so i think you should go for it!
I agree with Miss Jiminy.
Just let your sis know that you aren't yet comfortable being alone with the baby.
Let her know that you will help her care for the baby whenever she is there and when you feel comfortable, you can sit for her - just not yet.
I think your sis will respect you more if you're honest than if you decide to sit anyway and something does happen.
I would offer to have a fun night with her that night at her house. Watch movies and stuff and you can tend to the baby for her then.
Once the baby goes to sleep, you two will be able to enjoy yourselves still.
If the baby wakes, you can tend to the baby's needs. This way, your sis will know you are genuine and you really do want to help.
Hope this helps.
Don't do it unlesss you are 110% confident.
I don't get how anyone can give the advice "just do it" thats not a responsible answer. Maybe if you are giving the advice to "just do it" you should re-think your positions too. You should never be afraid or really nervous about a job. There is a difference between being nervous to meet a new family & make a good impression (normal) and being nervous about if you should be babysitting the kids.
If you are nervous about your sitting abilities don't take the risk- sure many times nothing will go wrong, but what if something does and you are not prepaired to handle the situation? Perhaps some jobs it's okay to just be "thrown in & you'll figure it out" but caring for a child especially an infant ( 8 weeks = 2 months) old. is NOT one of those situations.
Take the others advice and spend time getting comfortable with the baby. learn the routines your sister has, bedtime, how she calms the baby, diaper changes etc. as knowing what the parents do will make your job easier. I'm pretty positive that she won't object to you being more comfortable with her child, if anything she will appreciate it. In the long run it will make you a better sitter & you will be able to relax and have a nice time with your neice/nephew.