There are two use cases that you might find particularly useful.
In a brightly lit room, take pictures of your pants, shirts, etc. and select their main colors using the Chooser tool. Tag the colors according to what they came from (e.g. pants and shirts).
Select a color from an item you want to wear. From the Color Detail page, click the Harmonies button. Use the filter bar on the Harmonies page to limit the results to the colors you want. For example, if you choose a particular pair of pants, you might want to filter the harmonies list to colors tagged as shirts.
Another way to do this is via the QC button on the Chooser tab. On the settings page, make sure that the Closest setting is set to OFF. Then take a picture of a group of clothes you might want to wear together. Click the QC button and save a color associated with each of the possibilties, and then click on the item you are trying to coordinate with last. HueVue will determine how the colors that you chose coordinate with the last one chosen.
Make sure the that Closest setting on the Settings page is ON. Take a picture of the sample and the comparison chart together, preferably in bright light. Be careful that the lighting is the same on the sample and comparison chart.
Click on the QC button and then save a color associated with each of the colors on the comparison chart. Save a color associated with the test sample last. Then click on the Done button, and HueVue will display the sample color and the colors from the comparison chart in descending order, from best match to worst match. For your convenience, the number in parentheses after each color name is the order that the color was saved.
WARNING: DO NOT RELY ON HUEVUE AS YOUR SOLE MEANS OF JUDGING A COLOR MATCH IN CRITICAL SITUATIONS, ESPECIALLY WHEN HEALTH OR SAFETY MIGHT BE AT RISK.