www.mysql.org 's documentation is a good place to look for this type of information.
But this is how you would create a table with a field called "indexnum" which increments. This field must also be primary. I've also added two other fields, "realname" and "phonenum" for the example. "temp" is the name of the table.
CREATE TABLE temp (indexnum INT not null AUTO_INCREMENT, realname VARCHAR (60) not null , phonenum VARCHAR (60) not null , PRIMARY KEY (indexnum));
Cheers,