We all need creativity but it's impossible to conger on the spot. There is no "lightning in a bottle". That's why it's important to capture ideas BEFORE you need them, when the pressure is off. When your mind has time to wander and think. (And if you just thought to yourself, sounds great but unrealistic, you might have a "margin" issue, as in, you have none - that's a different issue altogether)
In the advertising world (at least back in the day) the creative team would pull out a "swipe file". It's what it sounds like: a folder stuffed with inspiration, color swatches, photos, anything and everything that is an idea or could lead to one. Today there are great options to do the same digitally. One great app/website I use is Evernote. You can save photos, text, video, and audio into files that you can tag (so you can find them in a search later) when you really need them. I don't collect ideas daily, but as often as i can. I also realize that it won't happen on it's own. You have to work the system!
So do you have a system to collect your ideas? Are you more of an old school file folder person or do you have some other system or app you use to collect? Either way, just be sure to a system! So next time you are put on the spot, you can have a place to go.