how do you open this sweeper to change belt

Several Model numbers.

Please list the model number so we can provide a link to a manual.

these are general instructions for a canister vac brush belt:

Disconnect cleaner from electrical outlet.

Check and remove hair, string and lint buildup

frequently in the brush and brush support areas.

If build-up becomes excessive, disconnect from wand and follow these steps:

TO REMOVE BELT:

1. Remove light cover and light

bulb.

2. Unscrew the cover screws.

3. Turn over.

To remove cover, insert screwdriver at

cover tabs on both sides and twist to

release tabs Quick Release

4. Turn right side up.

Press handle release pedal and lower

the swivel.

5. Tilt cover forward from back until

front snaps free.

Carefully insert and twist screwdriver

at each brush support to free brush

from base, Brush Support Base

TO REPLACE BELT:

6, Remove worn belt,

7. Slide brush supports off to check and clean brush support areas.

assembly,

8 slide washers and brush supports onto brush assembly.

9. Install new belt over motor drive, then sprocket.

10 Snap brush supports into place on base, Be sure brush supports are not upside down.

11 Line up front of cover and base.

Rest cover on front edge of base.

12 Tilt cover to back. Press cover firmly until side tabs snap into place.

Replace cover screws, light bulb and light cover.