Adobe Tutorial

How to make a photo grayscale in PhotoShop

Step 1: Open photo in PhotoShop
Step 2: Go to image on options bar
Step 3: Click mode
Step 4: Click Grayscale, a box will appear, click discard.
Step 5: Your photo is now in black and white.

Before and after



Then after you convert your photo to grayscale, you can then change it into a duotone.
Here is a tutorial: http://www.youtube.com/watch?v=ukautGwc1h4

Source: http://www.youtube.com/watch?v=ukautGwc1h4