Assertion is not something that
can be faked, however. You must believe that you can say "no"
to people. You must believe in yourself to be able to persuade
people to do what you want to do.
Notice that the indecisive are
those who do not have a backbone. They tend to please people,
and they have the tendency to hate their lives because they
cannot get what they want.
Cultivate respect for yourself,
believe in yourself, and realize that you can say "no"
to pushy people and even convince others to do what you want
them to do.
Cultivating respect for yourself
starts when you value yourself. Valuing yourself could start
from realizing and appreciating your achievements. Work from
there, towards valuing yourself for who you are. It is something
that stems from knowing who you really are, and appreciating
the "fearfully and wonderfully" created entity that
you are.
Having great confidence
and power in dealing with people is a lifestyle. Work
from confidence within yourself, and practice assertion with
people. From an experiment of learning when to say "no,"
it would then turn into a skill of being able to say what you
want to say, and getting people to follow what you say.