Pronounced - ul-zzz or Ll-zzzz. An easy way to say it is by trying to say the whole word with your tongue is touching the roof of your mouth.
Other forms of Ulz include extended "u's", "l's", or "z's". Each ulz can be customized to your choosing.
Cindy: Guys every time I fart it feels like burning. fml I shouldn't have eaten that spicy shit.
Example 2 - Lazy
While playing COD
Bro1: Yo bro, check her out
Bro2: Bro, that's my neighbor bro
Bro1: Dude I'd bang her any day
Bro2: Dude I'd band her again any day
Bro1: Bro, ulz
Example 3 - Drunk
After spending a whole day hosting Beer Olympics
Drunk1: Guys how the hell did the kegs end up on the roof?
Example 4 - Awkward
John: So, uh Bob...I sorta hooked up with your sister last night at your party.
Bob: WHAT@! YOU MOTHER FUCKER!@!