Roll the die and move. To take your turn, roll the die again and read the number that you rolled. Pick up your game piece and move forward that number of spaces. For example, if you roll a two, move your piece to square two. On your next turn, if you roll a five, move your piece forward five squares, ending up on square seven.
Some people play that you can only move onto the board if you roll a one, and if you don't get a one, you just skip your turn. This isn't recommended, since this can be frustrating for unlucky players.