I cannot state with utter confidence that I heard it used in the late '60s, as I was rather young, but it did seem to be around back then. Even “dweeb” is attested more than 50 years ago. It was one of those words, you just had to hear it used to grok what it meant. Kind of like “grok”.
FWIW, etymonline states that it originates in 1951 as US student slang (but also mentions it being used earlier by Dr. Seuss in 1950, I assume more as a nonsense word.)
Mostly cursing them as they walk home.
23 Ski-Doo! Excuse me while I vamoose this Dog and Pony Show…
Cyrus steps up to the microphone. “Caaan you dig ittttt?” All the gang members in the city applaud, except for Luther and his boys.
I know that from the adage, “teach your grandmother how to suck eggs,” meaning “don’t try to tell an expert how to do their job” and extended to “that’s so easy anybody knows how to do it.” The literal meaning is that two holes were punched at opposite sides of the egg and the raw egg sucked out leaving the shell intact and no mess.
Whether “go suck an egg” - an early politer way of saying “fuck off” - is derived from the same image is disputed. But I can easily imagine a point where sucking raw eggs was no longer a delicacy but disgusting. Something that “sucks eggs” would be equally disgusting, similar to “sucks rocks.”
Hmmm…etymonline does seem to point towards fellatio as being the meaning hinted at with the slang “suck”. I apparently have much too innocent a mind:
Meaning “do fellatio” is first recorded 1928. Slang sense of “be contemptible” first attested 1971 (the underlying notion is of fellatio). Related: Sucked; sucking. Suck eggs is from 1906. Suck hind tit “be inferior” is American English slang first recorded 1940.
“Nerd” and “geek” go back further, but their meanings have changed over the years.
Saying ‘I am down’ to mean you agree with something or would join in something has always struck me as a curious usage . A visitor from India has no idea what my daughter was saying , one night when we were discussing dinner options.
I guess the visitor though my daughter was feeling bad about something 
“I am down to” / “I am up for” is the flammable / inflammable of colloquial agreement to participate…
“My bad” for “my bad self,” usually said when someone makes a mistake or has said or done something embarrassing. I heard it in the 90s, but I don’t know if anyone still says it. I do.
Geez, Grandpa, when was your day? I’m 44 and do recall my parents being bizarrely insistent when I was in middle school that it “sucks” was vulgar before apparently realizing that it no longer had the same suggestive connotation to kids as when they were young, and no longer objecting when we said it.
I believe the more common usage is “down with” not “- to”.
Both are used - “DTF”.
I’m down to clown. Are you with it?
I still hear it and occasionally use it. I never knew it was short for “my bad self.” I just assumed it was nouning “bad” to mean “mistake” or “fault.”
My bad. You may be right.
Interesting fact: The first known public use of the phrase was by Louis Armstrong to Ed Sullivan in 1956. Louis Armstrong wished Sullivan a happy birthday and then corrected himself, saying:
“Happy Aniversary. My bad.”
Nice find on the early example of that phrase. Armstrong saying that to Ed Sullivan in 1956 sounds almost as anachronistic sounding as if Sullivan had replied “dude, that’s really cringe”.
Unless your name is Ash, and you’re fighting the evil dead with your boomstick.
Has anyone mentioned “neat”? I use “cool” and “neat” quite often.