first 7d doc shoot on sunday-what do i need to know?

just hired to make short doc for non-profit.

using friend's 7d w/array of nikon primes and 24-70/2.8 zoom.

i have never shot/directed w/dslr.

my friend will be operating. he is very familiar with his rig.

but what do i need to know about the 7d and dslr experience specifically in directing my three talking head exterior interviews?

what do i need to know in creating exterior supporting "b" roll?

there will be sound person on shoot.

any insights are appreciated.

be well

rob
smalltalk productions