Over the years I want them to first bush out more, then grow higher.

I was told by a friend that when you trim the tops, it makes the new
growth come out to the sides more and not get too woody, and nce they
are bushy enough then you can let them grow higher.

I would let them grow to plan height before top-pruning, which at that time
will indeed encourage side growth. By then, they will be touching eachother,
if you spaced them correctly.
Early topping just after planting can stunt or distort vertical growth in a
young hedge tree, and topping now may add shock/injury during winter. My
understanding that evergreens can be trimmed any time of year, but live in a
mild climate, so am not sure in your case.
If plants were container grown there is no need to trim now, unless there
was root damage in transplanting, in which case some overall trimming can
reduce shock due to undersized root system..
Frequent minor shaping is what to go for. You will get an even and luxuriant
growth that way. We trim our Cypress hedges 3 or 4 times during the growing
season, the last trimming about now. Since there is no growth from Sept to
April/May in your area, why trim in winter?
Given that these are just put out, be sure to limit frost by mulching well
with 4-8 inches of shredded bark or bark mulch, or hay. Don't forget to
water periodically during thaws, if there is insufficient snow cover this
winter.



- I live in Canada (Toronto) where we get some cold winters if that
makes a difference.