Today, it's okay to mix patterns or stripes! I often suggest laying clothing out on the bed or floor and see that it all goes together (or doesn't!). Keeping everyone "evenly weighted", that is making sure no one person stands out is still a good idea, but it's okay to have more than two or three colors. Feel free to add accessories. Does your daughter like to wear headbands with flowers? Choose one that works with your color palette. Can't find the right color top for yourself? Wear a statement necklace or a scarf that picks up an accent color in your palette.
As my clients pull their outfits together, I ask them to send me a quick photo via text or email to check out their choices all laid out together. Suggestions or changes can be made, if necessary, before the session. If I spot something that will work with a client's chosen palette while I'm out shopping, I'll send them a text with the location and price. You don't always have to purchase new clothing to make for a great session--shop your closet. We all have at least one thing that gets compliments. Whatever you end up wearing, love it and feel good in it--it will make all the difference in forgetting about what you are wearing and focusing on the real subject of the portrait--you!