Not Updated For Current Season
The masteries shown here are not yet updated for the current season, the guide author needs to set up the new masteries. As such, they will be different than the masteries you see in-game.
Singed is all about lane domination and pissing people off, to start out just focus on last hitting creeps. Once you get your catalyst, get aggressive. Some people take movement speed quintessences on Singed but I don't because, for me, the speed I get from Ghost and my ultimate is plenty, not to mention Force of Nature's movement speed increase.
but yeah against a balanced team this is typically how I build Singed and it's ****ing OP.