To clean the inner door glass, you will need to remove the door from the oven as shown in the image below. Place the door on a padded surface. NOTE: That oven door is heavy. Two people may be needed to safely lift that door off of the oven.
Once you remove the door, you can refer to the parts diagram for the oven to determine how to access the inner door glass. The doors on the ovens that begin with model 790.4812 . . . will vary. Here is a link for the Sears PartsDirect.com website that has oven parts diagrams:
Kenmore Electric Oven 790.4812 . . . Parts
. You will normally need to remove screws from the top trim and or handle. Screws will also have to be removed from the bottom and sides to separate the door components. That first link for a previous answer posted in the above response has a video that shows the basic procedure on one type of oven door. That video may help you with this repair. If you need more help with that process, reply with additional details and the full model number of your Kenmore oven.
If you get to the point where you need to have a service technician clean that inner door glass, you can schedule service through this link:
Sears Home Services