Hi...I'm a complete newcomer to this, so treat me as an idiot and I might just get the hang of it! Over the next year I'll be building a 10meter long display panel for a waterways festival and I want to include a load of LED's to help 'jazz-up' the display. I understand that I need to add resistors to the circuit, but do I need one for each LED? This would seem to be a lot of work, especially as I could well have as many as 20 to 30 LED's in each panel, all needing to be lit at the same time.