As always I am writing this for people who have no prior experience with LEDs, electrical and electronics works just like I never had before I did this. I will be posting a lot of pictures here and going into a lot of detail about making connections, wiring etc. So the people who know how these things are done may find it boring and unnecessary, but please bear with me.. it’s for the newbies. In order to understand LEDs and what kind best serves your needs go to my previous post – An Idiot's guide to understand LEDs It contains all the theoretical aspects of LEDs and in very simple language. Once you have a good understanding of what you need, read this post. Before starting this thread I would like to thank Milad, who helped me a lot throughout this tedious process. He is an awesome guy. I ordered the following things for Lighting from LEDGroupBuy.com: 12V 5A Power supply w/4PIN molex connector 4 pin Molex to 3 pin fan 80mm Fan Silencer Arctic Alumina Thermal Adhesive 5g Arctic Silver Céramique 2 - 25g CREE LED Optics / Lens (LED Type: CREE XT-E / XP-G / XP-E, Optic Angle: 60, Quantity in Package: 6 Pack) CREE LED Optics / Lens (LED Type: CREE XM-L, Optic Angle: 60, Quantity in Package: 6 Pack) CREE XM-L White (Color: Cool White (~6500K), Group: T5, Quantity in Package: Single LED) XML-CW-T5-3 Nos CREE XP-E Red (Quantity in Package: Single LED) XPE-RED-2 Nos CREE XT-E Royal Blue (Quantity in Package: Single LED) XTE -ROYAL BLUE- 4 Nos CREE XT-E White (Color: Neutral White (4500K), Quantity in Package: 6 Pack (5% discount)) XTE-NW-6PK- 1 (6 Nos LEDs) CREE XT-E White (Color: Warm White (3250K), Quantity in Package: Single LED) XTE-Warm White- 3 Nos DIM4 - 4 Port LED Sunrise/Sunset Controller V1.0 DIM4-R1.0- 1 Nos Fan 80mm- 1 Nos Hanging Kit for MakersLED Heatsink- 1 Nos Inventronics 40w driver - 700mA MakersLED Designer Heatsink Kit - Professional Grade (Length: 12 inch) Ocean Coral White (Optic Angle: 90°)- 2 Nos OEM Digital Multimeter DT-830B- 1 Nos Solder Tube 10g - 2 Nos Soldering Iron 60w- 1 Nos Solid Wire 24awg (300 volt) - 25 feet - Black- 1 Nos. Stranded Wire 24awg (300 volt) - 25 feet - Black Then I got some more stuff from Home Depot – assorted grommets zip ties water proof cable connectors two pin plugs some timers extra wire (in case needed) Before starting, make sure to make a rough sketch of how you would assemble your LEDs on the Heat sink. It is very helpful to refer to it when making the circuit. Without it there will definitely be a lot of confusion and chaos. A blueprint of this is available on LEDgroupBuy.com- Blueprint And here is mine for reference – People in India might be a little disappointed because it’s not available there. But I am sure you can speak to Milad if you really want it and can work something out. 1. To start, test each of the LEDs if they are working. For testing I ordered a Multi-meter from LEDGroupBuy.com. Connect the red and black wires (with pins on the end) to the multi-meter body as shown below. Now turn the knob to point to (diode) symbol. Gently touch Red wire pin to positive and black-wire pin to negative of the LED you are testing as shown below. If there are no defects on the LED, it should light up. In case it doesn’t light up, check the connections to the multi-meter again and whether its knob points to symbol. An alternative way of testing (without the multi-meter) is to use two AA size batteries and connect the positive of the batteries to positive plate and negative of the batteries to negative plate of the LEDs. 2. You must have received a no. of nuts, bolts and washers. Join them in as shown in the picture. Now place them into the grooves of the heat sink as shown below. For every LED you will require 2 sets of nuts, bolts and washers. Arrange these bolts in the same way as you have made in your blue print. This gives you a rough idea of the positioning of your LEDs. The Nuts and Bolts- You have to put them together in this way- They send many extra pieces- Then put them into the groves of MakersLED heat sink- 3. Pick up one LED and put a tiny bit of thermal grease on its back. Gently put the LED on its respective position on the heat sink and press it. Once in place, tighten the nut-bolt pair on the grooves. This holds the LED in its position. Do this step for all LEDs. Now all your LEDs are fixed on the heat sink on their respective positions. Make sure that you have placed all the LEDs in a way that you are able to connect all of them in series (- of one LED is connected to + of the other -- - + - + - + - + - + ….- +) Dont worry about the mess (I'm sure it the grease will mess up the heat sink). It can be wiped by a tissue later. 4. Now to wire all LEDs first pre-tin the connecting points of each of the LEDs. Pre-tinning is nothing but putting a small layer of soldering material on your connections. • Heat your soldering iron. When it’s hot gently bring it in contact with one end of the soldering wire. The soldering wire immediately melts leaving a drop on the hot tip of the iron. Gently place this drop on the small connecting plates of the LED you are connecting. Let it cool. It takes about 3-5 seconds to cool off. Do this for all the LEDs. This step makes it faster to connect wires to all twenty LEDs.