What is best way to cover everything with only one-umpire?

[SWFLguy]

with no one on base--- get onto the infield and
get good angles for calls !
with runners---- be loose up the 3rd base line--
keep most of your attention on lead runners
(they may score)
the more you work-- the more comfortable you will
be with finding those angles------
then you'll appreciate a base umpire all the more !!