The computer I have is a macbook, and I use photoshop 3.0 and I have an add on program called OnOne Essentials.
This shouldn't matter. but if you are new to photoshop and don't know how to make a black and white picture with color on it, here you go..
1) open up the image you want to edit, it must be color. I repeat, the starting picture must be color!
let's start with this.
2)Now, depending on the program and if its a PC or mac, you need to find the "layer" tab. Most likely ton the top somewhere near "File" and "image" =]
3)Now you need to select "New Adjustment Layer" and then select "Hue/Saturation"
Name it whatever you'd like, and press ok.
4)Slide the "Saturation" slider all the way to the left or change the number to -100.
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It should look like this last picture here. At -100.
5)Next select the paintbrush tool and change the color to black.
6) Now whatever you would like to be in color just draw on the picture like this;
7)If you would like to erase something, change the color of the brush to white to get rid of it.
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8) Now to save the file...it's probably easiest if you'd like to upload it to the web, to not save it like a usual document like "save as". Instead, try selecting File-Save For Web. Once that opens up, save it as a JPEG or GIF and then follow the normal steps.
This is for people who aren't used to photoshop, so it's fairly simple and easily explained.