@LauriBuell
Well let's be honest here.. There are multiple things that you actually can do wrong with LED pixels. Please work safely with those kind of materials that require power in such high Amperages and also make them safe for your installations / work if an audience member can get close to it / etc.
Just a few notes that I wish to drop about working with LED installations :
Get a great PSU from a manufacturer that is known for the quantity. (MeanWell for example has excellent power supplies, never get Power supplies second hand because you don't know what happended to them, or you can rely on them, etc)
With power comes great responsibility. A few things that you should do when you are working with LED pixels is
Get wire that can handle the current. (There are graphs online for this kind of shizzle. Look them up !)Protect your circuit from peak power by adding an fuse box and adding capacitors to your circuit. If you put your LED strip outside / in an environment with a lot of dust / etc use dedicated hardware that is designed to be used in such environments ! (You can get IP67 protected pixels). Please also use Connectors that are IP67 proof if you need to create an installation in such a environment.Never ever ever let your audience member have direct access to your power supply ! Make a nice box around it (With a few holes since we need to lose the heat !) that protects your power supply.Get some connectors that are rated for the power :)
About connecting your pixels :
Always first connect the GND to your pixels, after that your data line and as last the 5v+ (or 12v depending on your pixels)When you wish to disconnect do it in reverse order and you will never cause harm to your pixels ;)Add a resistor between your data line and your first pixel. This is to make sure that we don't do something stupid to our data line causing pixels to die :(
About production choices regarding pixels :
If you need something that is robust for an installation for example use a pixelstrip with double data lines. (WS2812b / WS2813 (5v logic) are pixelstrips that won't die when a single pixel dies))