Although I'm a bit tired I try to write something about the solutiuon.

First off, this was my first puzzle and I decided to make it rather spontaneous, so it was bound to be less thought-out.
I thought it would be fun for some of the SG puzzleholics, to find out what I want from them in the first place and then slowly add hints to give others a chance to participate - but enought about that , here's what I wanted you to do:

The sole purpose of this thread was to make you aware that there is a giveaway going on. (train music, poll with prices you can expect)

You had to realize that there's nothing for you to find here, and look elsewhere. And the "most" obvious place would be my Steam-Account.
At least that's where I wanted you to go :)

When you looked at my rather bland account you could actually see somethign right away

Games: 2131223423
Screenshots: 1
Guides: 1

If you went to Screenshots. You'd immediatly see a Rocksmith screenshot with a a easily visible 5 character code "Gi.._". with 2 now known characters "Gi"
If you did not knew what this means - you could not have moved on, that's why I recommended zelghadis guide for starters.

But heres where you use 5 character codes on steamgifts:

http://www.steamgifts.com/giveaway/GiVKM/

recognize the two characters?

So where could you find the other 3 ?

In the screenshot was a little hint: A song called "Wasteland" was highlighted. This at itself does not tell you anything.
BUT if you investigated my account a little further you could have clicked on "Guides" and would have realized that I wrote a Guide for
"The Waste Land". That could have set off your alarm - so to say.
Just scrolling through it would have given you the 3 missing characters, because I simply wrote them into the comment section
(I also gave a little hint to go to my screenshot section if you somehow managed to find those three first)

50% solved

Now that you managed to jump on the GA train, you were already eligible for 4 GAs

So for the second part:

When you were on the train, there were a couple things to distract you. But I pointed at least one - rather shady - hint out :
"Don't even think about this : "with a link to a version of Black sabbath's Rat Salad.
This wasn't such a great hint or extremely logical , but what I wanted you to do was to recognize the word RAT.
If you're a longterm user on this side you might have recognized jokes about gifting bad rats, if you did not .... well there was no way to proceed.
If you recognized it, you could have looked at my account and searched my "gifts sent" section for copies of Bad Rats (it really is a thing here! :>)

I've only gifted one copy of bad rats out of my 100 games I'd given away previously, So, when you would've clicked on that ( and at least scrolled through the comment section!!) you would have found another 2/5 character code along with a code in binary : 00110001 00110000 01010000

Translating binary can be done with this[bookmark!!] and this gave you 3 more characters : 10P

Now the trick part was to realize that these are not meant to be used with the other 2 characters, they weren't part of a code.
They just meant 10P(oints). So with this you could return to my "gifts sent" page and worked your way through all of my games( ~10-15) that had 10P as entry value - there was no shortcut to this.
I normaly just write "Good Luck" in my GA description but in the one you were supposed to find, I wrote something more .... acknowledging :

"When you're here, then you want to be sure that you are right. So?"

Now you needed to do your last task : mark the text and look into the source code ( this a common thing to do ) , you would have found an imgur link address hidden in it. This lead you to a picture with the three missing characters -> Success!!

Jeah, that's it. I hope you enjoyed trying to solve this.
If you couldn`'t find your way through this, i hope it gave you at least a glimpse at certain mechanics, people use to hide their puzzles.
I did not think too much about this one, I really just wanted to provide a little something for you to do on your weekend :)

https://www.youtube.com/watch?v=yJkmHQ2q--I

Congratulation to all Winners! :)

And have great week!