Pavers - care of
Go to a home improvement store and ask for some fine sand. Tell them what you are using it for. After you sweep it in with a push broom, water it like you would your yard. This will help pack the sand down and keep it from moving around. If it has been quite a while since you have done this, it may require a couple of applications.
FYI, my dad has done this for several sidewalks at his house. He first put the pavers down around 7 yrs ago and has not had any problems.
You really can't mess this up, so don't worry too much about it.