If you go to Settings > Configuration > Chem Sheet Templates, it will give you the ability to set up 6 custom auto-fill buttons for your different service/job types. This will give technicians the ability to fill out the Chemical Sheet by the push of a button.
When you click on one of the items from the list, you will then be able to edit the defaults for that service or job type, which are the auto-fill options under process->route when filling out the chemical sheet.
You can edit the options for the fields in the following locations:
Products used -- Inventory > Products
Area Applied -- Settings > Manage > Areas
Application Type -- Settings > Types > Application Types