Brands of the World:
Free Vector Logos
The first adj. layer is Hue/Saturation, which is set to -100 on the Saturation slider.
The second adj. layer is Channel Mixer, which you set to
Monochrome. You can sample anywhere within the image and adjust the red,
green & blue channels until the areas of the image are to your liking.
(the source channels when added together, should not exceed 100)
You can make more adj. layers such as a Levels, Curves, Contrast & even more Hue/Saturation adj. layers etc. just by sampling inside your image to make it pop-off the page.
I then save my PSD, so that I can always come back & re-edit if needed, I then flatten the image, re-name it, and save in the required format.
Tip #2
Text in Photoshop & Illustrator.
This idea is so simple, yet has saved me hours of typing.
Before rasterizing text in Photoshop or converting text to outlines/curves in Illustrator, duplicate those text layers, turn off the duplicate layers visibility (eye icons), & if the client makes changes, you don't have to re-typset all the text again. All you have to do is make the changes to those duplicate text layers.