You can start from a template:
fishing buddy
gal pal
backstabber
dumping ground
There are others, too,
or you can start from scratch,
customize everything—but
that costs extra and you lose
something in verisimilitude:
Can you custom-build your
actual flesh-and-blood friends?
Hardly. Templates might seem
artificial, but most real people
are pre-formed by the time
you meet them, anyway.
Consider this: When you get
a new green dinosaur from
a Mold-A-Rama in some cool
corner of a museum, you are
every bit as pleased with it
as if you designed it yourself.
Your new 3D friend will be
similar: all one color,
with that new toy smell.
Warm and pliable, at first.