For the sake of accuracy, it's NOT the "voltage" that can harm you, it's how much CURRENT that's behind it that counts, and the FREQUENCY of that current; (for reference, see the various pix all over the internet, etc., of Nikola Tesla sitting in a room full of multi-million-volt arcs, yet none are touching him, or the pix of his holding a rather large glass "bulb" that's been evacuated & coated with a fine white powder of who-knows-what-he-used, which lit up his lab only when he was holding it; NO wires at all. (He had an "antenna" type of arrangement connected to a then-considered "high-frequency" alternator, filling the room with high-frequency wireless energy, & when he picked up the glass bulb, he was the "receiving antenna" which got enough of the low-freq RF, (by today's standards), to radiate from him into the bulb to cause it to flouresce, hence the term we still use today, "flourescent" lamps. Only the frequency is different.)

I am presently sitting next to an evacuated glass globe with several thousand volts of around 16-kHz applied to it, & when I put my hand near or on it, the "streamers" inside the "Tesla Globe" follow my hand or fingers, but it doesn't harm me at all, & wouldn't even if there wasn't any glass between me & the high-frequency power-source causing the effects in the glass bulb; I don't feel a thing.

Look up "Skin Effect" to find out why a "microwave" oven, (they actually operate at upper-UHF frequencies), use a short length of otherwise-empty rectangular "waveguide" to get the output from the magnetron tube, at around 2-1/2-gHz or so, into the cooking area, which is actually a "tuned cavity", and you'll learn a little about why certain frequencies can pass OVER, but not THROUGH, the body, & let you do things like scare the daylights out of someone when you point one finger at a genuine Tesla Coil's output, and the finger of your other hand at them, with sparks streaming from the output-dome or torus of the coil to you, OVER your body, & then to the person you are pointing at, yet no one is harmed in any way. (Do NOT do this unless you KNOW what you are doing! Too many so-called "Tesla coils" can be heard to be humming at 60-Hz or 120-Hz, and THAT WILL cause a LOT of harm, or kill you; a GENUINE "Tesla Coil" operates at "High Frequency", which is what Mr. Tesla kept emphasizing, but even today, those who choose not to listen missed that little detail.)

I have a lot of fun on Hallowe'en, when I put a piece of candy to a kid's "goody-bag", with sparks flying off of my fingertips, complete with arcing noises.

I also put an HV-jacketed 100-megohm safety resistor in series with the Hi-Voltage wire connected to me somewhere under my jacket, and run the oscillator that runs the frequency of the step-up circuit to the output coil at around 16-kHz, so the CURRENT goes OVER me, and not through me.

And yes, I've been "bitten" by DC High-Voltage more times than I can count; it's why my hair is white, but I'm not nearly old enough to have white hair naturally... People who survive being hit by a lightning strike often have all of their hair go white; we don't know why, it just does, so that's why I emphasize that you must KNOW WHAT YOU'RE DOING before "playing" with any currents over a few microamperes. (Less than that shouldn't normally harm a normal human, regardless of voltage, BUT if someone has a latent heart problem, etc., even that small amount of current can cause a fatality, so always do your homework FIRST!)

Your "Instructable" is nice work, considering the tools you had to use & so on.

Now, you need to learn how to make the thing HARMLESS before "shocking" anyone; if made to operate properly, most people will swear that they "felt" the spark when they couldn't have, IF they saw & heard it...

The same goes with carefully shaping a piece of very cold ice to the the same dimensions as a cigarette, carefully drying the end, then touching it to the back of the neck of someone in a room full of people smoking cigarettes; they'll swear they've just been burned, until they realize there's no burn, and you show them the piece of (rapidly-melting) ice.

It's what their first instinct tells them was the most likely thing they felt; logic takes over a split-second later, when you showed them the piece of ice that actually touched them. (The same nerve-endings which transmit "hot", also tell us we're "cold", which makes that prank work.)

We used to call things like that "Party Tricks"; just make sure your "victim" doesn't have a weak heart!

The high-frequency, almost-no-current spark shouldn't even be felt; it's the eyes & ears that are telling the brain "You've just been shocked!", as long as you make certain that you can't feel it either.

Since this can't be stressed too much: DON'T do things like that unless you KNOW what you're DOING!

"Playing" with electricity can be entertaining & a learning experience, IF no one is harmed & you don't set fire to anyone or anything while you're doing it, and you know exactly what you're doing BEFORE you do it.

(I had 5-Watts of around 454-mHz go into my finger, {that's 454,000,000 cycles-per-second}, & while it hurt like mad, it wasn't enough to get out of me; I was the "output antenna", & the energy radiated equally out of the surface of my body, but the mark where it went INTO me took a few decades to finally fade away; a co-worker who should've known better, (but didn't), touched the output terminal of an operating 2.513-gHz transmitting tube while the transmitter was on, {that's 2,513,000,000 cycles-per-second}, and when he showed me the half-inch-long carbon-track on his finger, I asked him "which foot did it go out of?"; he took off his right shoe, and there was the matching carbon-track from the RF-burn on his big toe, where the 100-Watt signal had exited his body & gone to ground. Fortunately, he was young and the power had gone in his right finger & out his right foot; if it had gone across his hands, or through his LEFT side, it may well have caused his heart to stop, so be CAREFUL! when you're working with enough electricity to overcome your skin-resistance, so you don't become a statistic.)

We need good younger Techs & Engineers, but NOT dead ones, so I wish you well in your studies, and always remember to "do your homework" FIRST, so you don't become a statistic!

Not all frequencies will go over the human body, as evidenced by my getting thrown across the room & burned, and my co-worker getting burned at freq's in the millions or billions of cycles-per-second ranges, but there's plenty of info on the internet and other places to learn to "do it safely", so by all means, "read & heed" before "diving into an empty pool"!

Some key-words to search on are: Tesla, High-Frequency, skin-effect, "I.F.", "R.F.", waveguide, microwaves, millimeter-waves, wavelength; you get the idea.

Keep up the interest & experiments, & study what's going on to understand it, and you'll no doubt become a good Electrical Engineer, so experiment safely!