Here's how the strips will be laid out on the parasol. My parasol has 16 spokes, so I'm using 8 strips that are slightly shorter than the spokes (so they're not too crowded in the center). There will be a strip along every other spoke. The Circuit Playground Express will be attached near the outside edge, and the battery will live up in the center, out of the way. The on/off switch will be placed close to the outer edge as well.
This shows how to assemble the on/off switch using the clicky tactile switch and extension cable. Another way to do this is to simply use this JST cable with switch already included. You don't have quite as much control over where the button ends up, but it can save you several steps and some soldering!
If you've got the tactile switch and extension cable, here's how to set up the switch.
Find the end of your battery cable with the female connector (it's the one that plugs into the Circuit Playground). Clip the red wire a few inches from this end. Leave the black wire intact.
Trim the two leads coming from your switch. Strip a little shielding off the ends and solder to your battery extension cable. Now the switch will control power running through this cable.
Put this aside for now. We'll add it halfway through the assembly of the NeoPixel strips.
Measure against your parasol to decide how long you want each strip to be. Cut 8 strips to length. Count your LEDs on each strip and multiply by 8 to get your total number of LEDs.
As you lay these out, pay close attention to which end is IN and which end is OUT. You must connect the data wires in the right order or the strips won't work.
It may save you time if you trim the strips from the middle instead of from the ends. It can be tricky to solder wires securely to these strips, and there are already wires soldered to both ends! You can take advantage of this and use those wires. Just trim out the middle few pixels instead of chopping off the ends of the strips if they're slightly too long for your parasol.
Cut a piece of clear heat shrink for each open strip end. Slip it over the silicone tubing on each strip, but don't shrink it down yet -- it's just best to get all the heat shrink on before you start soldering so you don't forget it. Later we will fill the ends with hot glue and shrink the heat shrink to create a waterproof and dust-proof seal.
Time for soldering! Make sure you're starting from the IN end of the first strip. If you're using the pre-soldered wires, trim them to about 2-3 inches. Solder red to VOUT, white to A1 and black to GND. Trim off any other extraneous wires.
Grab your 4 strand ribbon cable and find the wire with the white stripe on it. This will always be our 5V wire (so imagine it's red!). Remember: striped wire = red (5v) power wire. Be consistent with this or you'll end up with a world of hurt.
Grab the fourth wire (the one on the opposite side from the striped wire). Pull it off the ribbon cable entirely, so that you now have a 3-wire ribbon cable and a spare black wire. Save the spare wire for another project.
Cut a 3-4" piece of your new 3-wire ribbon cable. Solder the striped wire to 5V on the open end of your first LED strip. Then solder the middle wire to OUT and the remaining wire to G.
Take the other end of the ribbon cable and solder the striped wire to 5V, the middle wire to IN, and the remaining wire to G on your second strip.
Plug your battery into the Circuit Playground's battery port and test to be sure your strips light up. Test each strip as you go to make sure all your solder connections are good and solid. One bad connection will cause all the lights downstream to fail.
Unplug your battery before making any more solder connections. The fastest way to fry your Circuit Playground is to solder on strips while the power is on.
Notice how the first strip only needs a few inches of wire at the end to connect to the next strip since they'll be close together near the center of the parasol. The second strip will need a longer run of wire since it will be going along the outside edge of the parasol. You want to get as close as possible to the right amount of wire, so you don't end up with a lot of extra wire flopping around.. but you also don't want the wire pulling taut when you open the umbrella.
Cut a longer piece of ribbon cable, the right length to reach to the third strip along the outside edge of the parasol. Solder the wires in the same order as the strips before.
If there are pre-soldered wires on the end of your strip, you can splice the ribbon cable to the wires instead of soldering to the strip itself. Be sure your striped wire goes to red, the middle wire to white, and the remaining wire to black. Plug in the battery and test!
Solder on your fourth strip with a shorter piece of ribbon cable. Then solder your longer ribbon cable to the far end, in preparation for going to the fifth strip. At this point, STOP and take a break! We're halfway through the strips, and it's time to add the battery and switch connections.
Find the switch assembly you made earlier. Snip off the female JST connector (the one that fits into the Circuit Playground).
Also snip the striped wire and the third wire (5V and G) on the ribbon cable coming out of strip #4. Leave the middle wire (the data wire) intact.
Splice the wires from the battery cable as shown: the striped wire will get twisted with the red wire, and then both striped wires get soldered back together with the red wire incorporated. The black wire will get incorporated in the same way into the third wire from the ribbon cable.
Plug your battery into the other end of the battery extension cable and flick the switch. The lights should turn on and off. If they don't, check your wiring again!
Continue wiring up the last 4 strips the same way you did the first 4. Once all 8 strips are solid, and turning on and off nicely with the switch, seal the ends of the strips by tugging the clear heat shrink you put on earlier over the solder connections. Squirt some hot glue into the end of the strip, then use a heat gun to shrink the heat shrink down around the wet hot glue. When it dries, you'll have a nearly unbreakable connection that's weatherproof and dust proof.