How do you take bolt out of mauser k98?

First, pull the bolt back like you would when you are reloading. On the left side of the gun, there is a steel rectangular button on the end of the reciever right where the bolt is. Pull on it and the button should pop out but not totally come off the gun. Stick your finger in it so it doesn't go back to where it was. Then, pull back on the bolt and it will come out. When you want to put it back in, just do the same thing to the button and push the bolt back in.