Seals typically slide into a channel at the bottom of the door or they are placed between the base of the door.
Replace seal bottom of shower door.
Next cut a length of seal strip slightly longer than the section you are replacing.
Remove the old sweep or seal clean the glass edge of the door use a glass safe scraper to remove any dirt or residue and clean with your favorite glass cleaner and a soft cloth.
When replacing the shower door bottom seal you will need to fully open the shower door to access the seal.
Inspect the bottom of the shower door to determine the plastic seal attachment method.
The seal should be tight and take some effort to get seated correctly.
If you will be replacing more than one door seal replace the bottom one first.
See image below once the seal is removed you will need to clean the bottom of the shower door as hard water buildup is most likely on the bottom of the shower door.
Carefully remove the old seal from the door by sliding the seal downward.