You gave us no information about what you are using with the sorbate.
Kit, frozen grapes, sweet wine, what?
You can mix the proper amount of sorbate with a small amount of warm water or a small amount of your wine; either case just enough liquid to fully dissolve the sorbate; then add to your wine while stirring. Never just dump the sorbate straight into the wine.
The use of sorbate sometimes can be optional, unless your resulting wine is going to be sweet. However, we will need more info before we can advise about leaving it out completely.