how does this fasten to the toilet

The owners manual is included with the following instructions for tool free assembly: Remove contents from carton. 2. Assemble frame by inserting armrest section into two frame support sections by depressing brass push pins on armrest and inserting into receptacles. Note that front of armrest should correspond to section with rubber tips. When in place, push buttons with snap into place. Insert “E” clip into back of frame to secure armrest to frame. Repeat for second armrest. (Figure 1) installation instructions 3. Remove existing toilet seat from toilet. Be sure to save the existing screws as they will be needed to attach the frame bracket and re-attach the seat. (Figure 2) 4. Place frame bracket on toilet with tube on bracket closest to tank. Position toilet seat and cover over the frame bracket and secure in place using the screws mentioned in step 3. (Figure 3) 5. Insert armrest into the now-attached frame bracket, making sure push pins protrude all the way through the adjustment holes. Armrests can be adjusted by depressing push pins and setting to desired width. 6. Place rubber tips under the toilet seat. The weight of the user will secure frame in place. (Figure 5)