Summarize:

If your bat develops any cracks during the knocking in the process, you can fill them with liquid super glue. Purchase the superglue online or at a hardware store. Squeeze a small amount of the glue into the crack and spread it around with the cap of the glue. Let the glue dry for 24 hours before using the bat. You'll want to allow your bat to absorb all of the linseed oil completely, which will take about a week. When it's completely dry, you can use the bat as is or apply a face tape to the bat to prevent cracks while you play. Keep the bat out of direct sunlight as the oil dries. Cricket bat face tape can be purchased at a cricket store or online. Peel the back of the face tape off and lay the sticky side down on the flat side of your bat. Wrap the edges of the tape around the edges of the bat. Use a credit card to smooth over any bubbles in the tape. You can purchase a toe guard online or at a cricket store. A toe guard is made of rubber or plastic and fits on the end of your bat. Apply superglue to the back of the toe guard and onto the flat end of your bat. Glue the toe guard to the bat and cut off the excess around the bat with scissors. A toe guard will prevent water from being absorbed when you hit your bat against the wet ground.
Use liquid super glue to fill in any cracks. Let the bat dry for a week. Apply bat face tape to the bat to prevent future cracks. Glue a toe guard to the end of your bat to repel moisture.