I am currently working on an engineering project for class, and I need some help with the wiring. I am trying to build a mask that uses a photoresistor to change LED colors, with white LEDS in a light room, and red LED's in a dark room, and a servo motor activated by a button to spin the mask. because of this I am trying to connect everything to the Arduino Uno board without the use of a bread board or other wiring plate. I have worked out the code and basic structure in TinkerCad, but i didn't know if I could get the LED's to work if all the ground wires were soldered together then attached to ground, and the same thing for the grounding and power wires of the servo, button, and photoresistor. I do have access to a soldering kit, but I have little to no experience, so I wasn't sure if learning to solder everything together would even work, and I didn't want to start and then end up ruining everything on accident. If theres a better way to wire it, or if learning to solder is the right move, please let me know! Here is a picture of my current wiring mess on TinkerCad (orange wires all go to ground, dark blue to the 5v pin)
I like kits of proto-boards like this. You can pick the size to fit the use.
How will the Uno be powered in the end use?
You can solder all of the grounds together and connect to one ground on the Uno.
Powering the servo from the Arduino 5V can be a problem. The servo can pull the 5V rail voltage down to the point that the Uno resets. Use something like a 4 AA cell battery pack and connect the ground to the Uno ground.
I have the starter project kit so I was planning on using the battery attachment. I didn't know about the servo issue, I will definitely look at that, thank you.
and thank you for the proto-board recommendation. I don't think it'll come in time for this project, but I will definitely get some for future builds
Unfortunately the UNO is pretty impractical for such (most in fact) projects.
The smaller Nano would be more practical as it easily mounts on stripboard (or protoboard) which facilitates multiple soldered connections to each pin and makes a durable assembly.
If it is going to be battery powered, the Pro Mini does not have the USB interface (you provide it externally) so that does not waste power though compared to the current the servo draws this is pretty minor.
at "wokwi.com" it is possible to show and copy component&wiring list (diagram.json). so we can edit it and give you back with corrections. after that it is possible to simulate the sketch.
My suggestion based on your statement that the proto boards are not available in your timeframe.
I see the drawing but do you have any solid wire that will connect to the female headers on the board? If so you can run wires to the UNO connector and collect the grounds and twist them together. If you have solid wire they might stay together long enough to prove your success. If not you can go to a Home Depot (or eq) and get some small wire nuts or crimps. Wire nuts are a plastic cap with an internal tapered spring you simply twist them onto the wires and the internal spring holds the wires together.
OR
If your wires are long enough you can afford to cut some off, then try soldering them. You may find its not as difficult as you think. And if you mess up you can always just cut the messed section off and do the above.
If you do try soldering, each joins should take < 5 seconds usually. Simply put some solder on the soldering iron tip then use it to heat the joint adding solder as the joint heats up.
There are a number of youtube videos that would be of help.
If using the cheap sets of "Dupont" style jumpers, try this with just one wire first. Some of the Chinese garbage turns out to be Aluminium and cannot be soldered. 
Breadboards are called breadboards because back in the day, people used to hammer nails into their mom's wooden bread board and wire wrap everything.
Point is, for something relatively electrically simple like what you're doing, ground is ground. You have lots of options, including a clean, shiny finishing nail as a ground lug if you don't have a terminal block or something similar. To put this concept into something easy to relate to, consider an automobile. Take your multimeter out, pop the hood and put the positive lead on the positive battery terminal and the negative lead anywhere that's good exposed metal in the engine compartment, like you would with the negative on a booster cable to the car that needs the boost. You'll read the same voltage with the negative lead on the chassis as you would with it touching the negative battery terminal, because everything in a car's electrical system ties back to chassis ground. Good luck on your project!
Just use Breadboard for the same
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