If you're a parent and you're over 50, your kids will not be duped into thinking you're cool if you imitate their clothing style, adopt their slang and embrace their culture. Maybe you were hip in 1969 when you were rolling around in the mud at Woodstock, but the mere fact that you're now over 50 means that achieving the level of coolness that your kids and their friends enjoy is an impossible goal for one reason - you're over fifty. And yes, if you understood what I meant by the word "hip" you've just dated yourself.
For starters, please stop using the word "awesome". You should know better. The Great Wall of China is awesome. Ordinary, mundane things are not awesome. If you're an educated adult, you're probably aware that the English language contains more than one adjective. Try to imagine that it's the Sixties and your parents are overusing terms like "far out", "outa sight", and "groovy". Dumb as those words are, they were our words.
Stop wearing torn jeans. On the kids, they look cool; on you they look like you fall down a lot.
Get rid of the flip flops and wear sensible, adult shoes. Your kids have lovely, smooth, young-looking feet; yours are probably veined or bony or swollen or bulging with unsightly bunions. If you're a fifty-year-old guy, you may even have a trace of toenail fungus. Who wants to see that? Going back to the Sixties again, try to imagine your father going to the office in Frye boots.
If you grew up during the Golden Age of Rock, you can't possibly like hip hop or rap music, so stop pretending that you do. Snoop Dog will never be as good as Led Zeppelin. Paul McCartney should retire. And let's face it -- there's nothing more idiotic than an adult jumping up and down in a mosh pit like a gray-haired jack-in-the box. For one thing, you might pull a muscle or go home with a stress fracture because you're not fifteen anymore and your limbs have been through half a century of wear and tear.
Dad, the three-day stubble is cool, but not if it's gray. You'll just look like you forgot to shave. Mom, Lady Gaga can get away with those hairdos; you can't. People will think you escaped from an asylum.
In your vocabulary, the term "hooking up" should only be used to describe a process involving a pick up truck and a speedboat. And if you're old enough to be a member of AARP, the word "dude" should only be used if it's followed by the word "ranch".
Here's the bottom line: If you've been a good parent - loving, nurturing, supportive -- your kids will always think you're cool, but in a different, more significant way. Trying to be their parent and their cool friend is hopeless and unnecessary. You had your time to be cool; now it's theirs.