OMG, in this instance stands for Oh my God, meaning the speaker is amazed at something
LIEK, is a bastardization of the word "like". in this case it is used to segway into the term WTF-
WTF- means "What the Fuck" curiously, the question mark is absent, and the acronym can be used as a statement or question.
OMGLIEKWTF- Wow, like, what the fuck?