@Anastasios
Thanks for this very useful feedback, this way I might improve my guide and I wasn't completely sure about some things which include masteries, I mostly just pick some stuff which seems kinda ok. About the items, as I told in my guide you can change it a bit. I considered using the catalyst, but I'm not really a fan of the Rod of Ages. The Catalyst would defenitely be a good early item if you buy the Banshee's later on though. As for the GP/10 items I really like them for the immense gold help and they give you a good lane advantage and of course you can always choose to upgrade them. I make sure that I sell them as late as possible though. I will try to improve my guide at the masteries and items a bit. Thanks for this useful feedback.

@TimoBouwerzz
I basically chose that name for fun while making it and didn't realise it when I published this build. Will defenitely change it. About tips in teamfights and laning phase I thought about that and I will add that I think. Thanks for your vote and feedback.

Skipping Catalyst is a dangerous path, but it can definately work.
However, GP/10 are of questionable use to Singed if you don't buy their upgrades (Randuin's or Shurelya's). He can farm very, very, very easily, and he gets a ********ton of assists.
Splitting the masteries is good, but Evasion is horrible, and Initiator isn't as worth it as the huge CDR provided by Enlightenment . Meditation is alse very "meh" on him due to the massive mana pool you normally build. Have you considered a 3-tree split? Meaning getting Arcane Knowledge , Veteran's Scars , Swiftness , and the rest points spent on defense (usually), taking Vigor , indominable, or something else.
I also strongly suggest you start with a point in Fling for early aggression. People severely underestimate Singed's lvl 1 damage. Just consider that he has the 3rd (i think) highest starting AD, and Fling also becomes invaluable in a lvl 1 teamfight (during e.g. an invade). You can also get a fling in the tower, if your opponent gets way too close.
Also, boots are definately an excellent starting item, as it provides you with a lot of mobility for kiting and running and dodging skillshots, but regrowth is also decent if you face a super passive lane ( Nasus or somehing) without a ganking jungler (like yi, but not maokai or lee).
Overall, the completed build is completely viable, and quite good, but the inbetween need a (small) rethinking.
P.S. Welcome to MOBAFire :)

Good guide, good build but I suggest changing the name because its kinda simple if you know what I mean, maybe its an idea to add what you need to do in teamfights or in laneface!
Good luck!