Installing or replacing a garbage disposal is a fairly easy task requiring no special skills. If you are replacing a garbage disposal with a similar model, your task may be a very simple one. You may be able to simply remove the old unit and put in the new one with a minimum of installation steps. If you replace it with a significantly different model or are installing one for the first time, the task may still be easy. Be sure to first check the installation dimensions to make certain it will fit in the available space.
Before beginning installation, unplug the garbage disposer or shut off the power at the fuse box or breaker panel to avoid injury.
Note: Your city, county or other governing body may have specific regulations relating to the installation of a garbage disposer. Be sure to check, understand and comply with all relevant local codes.
Note that for any installation a grounded electrical supply is absolutely required for your safety. Do not install a garbage disposal without proper grounding.
Here is an outline of the steps to install a garbage disposer: (don't worry, more details follow)
Remove the old disposer
Replace the sink flange (may be optional)
Fasten the upper mounting assembly to the flange
Punch out the dishwasher plug (if applicable)
Connect the electrical wiring to the disposer (with power OFF)