Great color themes in Office are not a random collection of swatches. Each spot in a color theme has a job. Once you learn those functions, great color themes will roll out from your office.
I'm always astounded to hear a Office "professional" who says "I don't use themes." I'm amazed because in modern versions of Office it's impossible to not to use themes. If you haven't set a theme for your template, then you're using the default Office theme. Whether you like it or not! Themes are an integral part of Office, so you'd better learn how they work.
When you create a color theme in PowerPoint, the color set is added to the theme1.xml file in your presentation and it's saved on your computer. If you create a second color theme, that theme is also saved to your computer, but it replaces the first one in your deck. When you're using the user interface, each Slide Master has only 1 theme at a time. So for more color themes, create more slide masters. If the color theme is for a special purpose, like differently-colored charts, the extra slide master might have only 1 slide layout. That's less confusing for users.
Great Color Themes: Color Slot Functions
Almost every slot in a color theme has a PowerPoint function, a job that it fulfills for the program. If you don't know what these are, you'll place the wrong color in the slot and get a result that looks weird in the program interface. Needless to say, this doesn't help your professional cred with your client.
Here's the Color Theme editing dialog as seen in PowerPoint 2016 for Mac. In Office for Mac, you can only create color themes in PowerPoint. In Windows versions, you can create them in any Office program, though there is a good reason why you should still use PowerPoint.
The following advice covers standard presentations that have a light background and dark text. If you're going for the mysterious Mafioso look with a dark background, then reverse the following instructions putting text colors into the light slots and backgrounds into the dark ones. Oddly enough, when PowerPoint imports a theme exported from Word for Excel, it will default to the Mafioso look. This is the good reason why you should always export theme files from PowerPoint, where your choices for background and text are explicit and that information is preserved in the theme.
The first 4 colors are for text and backgrounds. Although all 4 are called Text/Background, that just to accommodate the occasionally light text on a dark ground, as mentioned in the previous paragraph. In reality, Dark 1 is the main text color. If you have black text in the deck, leave this set at black. You should only change this if you have no black text (Please dont't tell me you're doing that trendy look of black text that's dark grey and makes it look like your printer ran out of toner. Eww.)
You may have a secondary text color for headings. That must go in the Dark 2 slot. Not in Light 1! Not in Light 2! All text colors go in the dark slots!
Light 1 is for background colors. Most of the time, this is white, so leave Light 1 set at white. If the design calls for a different background color than white, set it here.
Light 2 is the only slot in the theme that doesn't have a secondary job. You can make this slot any color! It doesn't matter! Woo-hoo! Let's hold off, this is a good spot for an extra color that doesn't fit elsewhere.
Accent 1 is the default color for inserted SmartArt, Text Boxes and Shapes. Almost all the time, you will make Accent 1 the primary corporate color. For our company, PMS 481C is the code color, so Accent 1 is the RGB equivalent in all our company themes.
If the company has a secondary brand color, Accent 2 is the logical position for it. So what about Accents 3 to 6? You're thinking "Hey! 4 empty slots! Throw some colors in, we're done!" Not so fast, junior.
Great Color Themes: Chart Fills
The set of Accent colors have a huge responsibility of their own: chart fills! I've created a color sequence to show how these are applied by PowerPoint.
Office programs fill charts using these 6 six colors in sequence. So when you're designing, it's best to know what that sequence is. The colors will be used in the same order:
If there are no additional colors in the design standards, we create a pair of lighter and darker variations of the brand colors for Accents 3 to 6. But don't just create a pretty series of swatches! Is the chart readable when printed on a black and white laser? Can color-blind people read it? You're a Designer! You're supposed to be thinking of these things! The rule of thumb is to alternate darker and lighter colors in a sequence so they can be distinguished from one another even in monochrome. Not sure? Test it!
Of the 12 colors in the theme, only the first 10 are accessible to the user in color picker dialogs. The last 2, Hyperlink and Visited Hyperlink, are applied automatically when the user inserts a hyperlink in the document. I usually use 2 of the theme colors for these, rather than Microsoft's standard colors. If there's a blue, that's a good choice for the hyperlink, it's a visual cue. The followed hyperlink can be a lighter grey or other tint, if there is one in the palette.
Great Color Themes: Recognizing Trouble
Before shipping the deck, here are a few quick tests you should be performing to show any color theme problems:
If either of these look odd, you probably have a color theme problem. If the text or background of either the chart preview or SmartArt don't match the background of the deck, you've probably inserted a dark color into the Light1 slot
Most of the autogenerated table combinations in this example are hideous and unworkable, sure sign of a bad color theme. You may also see a table style preview that looks different from the actual table. If the table preview shows a different color for table text (it will just show colored lines, not actual text), then the colors in Light2 and Dark2 have to be switched. Another problem indicator is if it appears you are selecting one color in the picker, but the actual color applied is different.
If you see any of the above symptoms, take the time to fix them and do it right. Your client will notice these glitches and you won't be able to 'splain them away.
The general method to fix these issues is to put the theme in correct order, then go through the entire deck starting with the Slide Masters, correcting the colors back to the designed appearance. This effort isn't too bad if it's a single template or theme you're correcting. Groups of finished presentations are a different matter that need a more automated approach. Next time, I'll be writing about how to repair presentations with a bad color theme, using XML Hacking.