Playing with flashing settings - with and without a button

I am trying to build an RGB circuit where I can program different flash settings into one script. I currently do not have a button, and am in the process of looking for one. I would greatly appreciate recommendations. Until then, I am trying to find a way to possibly use resistors and/or transistors to mimic a button. I would appreciate advice on that as well.

My idea is to turn on a flashing pattern with a button push, and that button push can be used to cycle through multiple settings of flash patterns, setting a flash frequency and brightness on each LED. I hope to be able to program it such that pressing and holding the button will shut off the lights, while pressing will just be cycling through the settings. Any advice on how to do this without a button?

You can definitely rig up a button with some paperclips, wire, etc. I often just use a jumper wire as a temporary button substitute rather than digging a button out of my parts stash.

If you have any dead electrical devices lying around, you can check to see if it has is a button you can salvage.