How can I use Pantone, TruMatch, CMYK or other colors in PowerPoint?
Your client has given you the color specifications for their presentation but they've specified them in Pantone (PMS), TruMatch, CMYK or some other color system. PowerPoint only accepts RGB.
How do you convert these colors into RGB in order to use them in PowerPoint?
Pantone is used to specify colors that will be printed on a traditional printing press using special inks supplied by (surprise, surprise) Pantone. Using these inks is the only way you can be certain of matching a specified Pantone color.
Pantone used to sell an add-in for PowerPoint and other Office products that let you choose Pantone colors (or rather their Pantone-approved RGB equivalents) from within PowerPoint. You may want to check Pantone's web site to see if there any new products that'll make it easier to work with Pantone colors in PowerPoint.
If you have CorelDraw, Adobe Illustrator or any other illustration or image editing program that can work in Pantone/TurMatch/Etc., CMYK and RGB, you can create your own conversions.
First, turn off all color management, or the conversion won't be correct. How do you know when you've turned CM off for sure? If you can convert back and forth from RGB 0, 0, 255 to CMYK 100, 100, 0, 0 rather than having the values slowly change with each conversion, you're good to go.
Now in the program's color dialog, choose PMS, pick the color you want to convert, then change the color model to RGB.
You can use the same technique to convert from CMYK to RGB. TruMatch colors are actually CMYK values, so again, the same technique applies.
Will the conversions be perfect? Sometimes they'll be pretty good, sometimes not. What looks good on your computer may be a bit off on somebody else's system and may print as something entirely different on various printers or even with different printer settings and various printer paper choices.