The most important thing you can do is remember that she's 8! She's a kid and kids sorely need to have fun! I would encourage you - and her - to approach the game for the fun of it. Even as she gets older, in any sport she plays, play it for the fun of it!
Don't focus on wins & losses and don't worry about playing time. Make sure that the kids she's with become her friends if they're not her friends already. Do things away from the soccer field with her teammates that are purely fun - like team sleepovers or going to eat ice cream.
Make sure that the coach - it'll likely be a volunteer coach - coaches "positively". You want your kid playing for a coach who looks for good in all 8-year-olds - absolutely no negative comments directed towards any of them, especially on game days.
Foot skills - fundamentals - will indeed make the difference between feeling comfortable on the field and not. No 8-year-old wants to hear strategy, nor can they comprehend it - they just want to kick a ball and be with their friends. Juggling skills is a great way to get comfortable. But don't push too hard - this year, since it's her first experience, juggle with her and kick with her but always remember the mantra - "is it fun?"!!! Foot skills will come next if she decides she wants to get better.
Another fun thing is for you to be the goalkeeper and let your kid shoot on you. My kids took special pleasure in beating their Dad, especially when I complimented them in front of Mom. When they were young, I might have been a tad slow "keeping" their shots so they could enjoy success but they never noticed. I guarantee I couldn't stop either one of them now if I absolutely had to!
The vast majority of kids starting out in soccer will not wind up with a soccer scholarship - don't even start out with that expectation on your kid. Make it fun and enjoy the memories. The time goes by too quickly.
