What is the best way to mount a bunch of leds?

I am making a light with a mixture of different colors using digital potentiometers to individually control each colors brightness. What would the forum consider best to use to mount all of these lights onto? Does what I mount on really affect anything because the heat level is still so low even with the high number of lights? Should I mount them on the cheap metal 5mm LED mounts they sell at any electronics place or should I mount them directly onto a board of some sort?

How many LEDs? Does it matter what it looks like?

When you have lots of LEDs a PC board makes wiring a lot easier, but you'd need to have a board made. A perfboard doesn't save you much work over point-to-point wiring, but it's mechanically more solid. You can combine a PC board and some sort of front-panel mount if you wish.

I've used a few hundred of [u]these[/u] over the years for front panel mounting. If you are mounting several in a row or in a rectangular pattern, you have to be careful & precise with your drilling. And about half the time, I solder the current limiting resistor directly to the LED and insulate with heat shrink tubing. (I like to use clear heat shrink so I can see the resistor... Otherwise in the future, I might forget it's there.)

Does what I mount on really affect anything because the heat level is still so low even with the high number of lights?

Regular 'ol ~20mA (~40mW) LEDs don't generate much heat and heatsinking is not important (even with lots of 'em, the heat is spread-around a bit). "High power" LEDs rated at 1W or more usually need a heatsink.

Great thoughts sir. To be more precise I want to mount them in a 3 x 3ft area as to spread the light in the right way. Also some are not 5mm but are slightly larger and are 3W but are already soldered to a heat sink star base. These lights will be disbursed in between the 5mm leds.

PS Also 225 .02A 2V red leds and 24 3W blue leds