LEDs

Determine the direction the data will travel through your LEDs, marked by an arrow. On my pixels, I see an arrow pointing towards the pixels on one side. Based on this, find the initial point where the data will enter the pixels. 

Find the matching 3- or 4- wire connector that fits into this side. If it's connected to the LEDs, remove it. 

Prep

Locate 3 or 4 jumper wires and some small pieces of heat shrink. I've used matching color wire and the best possible colors I had on hand for heat shrink. 

Cut one male side of each jumper wire off and throw out, or add them to your pile of maker confetti.

Solder

Strip about 1/2" of the open ends of each of the jumper wires & the open ends of the LED connector wires. 

Secure some heat shrink on the wire and use your fingers to twist the the matching wires together. 

Solder the wires & heat up the heat shrink and set aside.

Button

Locate 2 jumper wires and some small pieces of heat shrink for your button. 

As you did above, cut one male side of each jumper wire off.

Strip about 1/2" of the open end of each  jumper wire.

Secure some heat shrink on the wire and use your fingers to twist the wire onto opposite (diagonal) legs of the button. 

Solder the wires to the button and heat up the heat shrink to secure it below the button.

Optional

Follow the Ruiz Brothers great learn guide and create a DIY On/Off JST Switch Adapter for this project.

Photo credit: Ruiz Brothers