Hi Jim,
Unfortunately there is no “one answer applies to all” solution when it comes to precomposing as each situation is different. I’d recommend that you either read a book or watch a tutorial that covers the subject of precomposing in detail. If you like watching training movies then the “After Effects CS5 Learn by Video” product by me and Todd Kopriva covers nesting and precomposing in detail. Or there’s Trish and Chris Meyer’s wonderful “Creating Motion Graphics” books that also cover this in detail.
Hope this helps.
https://www.amazon.com/dp/0321734866?tag=agelatayloran-20&camp=14573&creative=327641&linkCode=as1&creativeASIN=0321734866&adid=0GDDCHTKJK1Q4GA2FVMB&
cheers,
Angie
Angie Taylor animation & illustration for television, film, web and devices
https://www.angietaylor.co.uk
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