An example of a joke for a 60th birthday party is: "Turning 60 means...the candles on your cake set off the sprinkler system." Another one is: "Turning 60? Look on the bright side: you're still younger than Mick Jagger."
One joke at a 60th birthday party is that at age 60, people can no longer drive faster than their age. Another joke is, instead of adding berries to morning cereal, 60-year-olds can sprinkle prescription pills on it, and their joints snap, crackle and pop more than the cereal.
A humorous remark could be to suggest putting LED lit candles on the cake, otherwise all the fumes might accelerate global warming. Another joke is 60-year-olds' lives are just as energetic as they were during their twenties, but at age 60, they have people in their twenties doing most of the work for them.
Another humorous idea for a 60th birthday party is to have a celebrity-style roast. Each guest should know about the roast, and should have a humorous story or joke to tell. It is advisable to make sure that all guests know what is appropriate for the person being roasted to avoid offending him. In some cases, it may be best to have only one person speak at the roast, preferably the best friend of the person turning 60.