"countless ways of" is a correct and usable phrase in written English.
It is typically used to describe an infinite or uncountable number of ways to do something. Here is an example: There are countless ways of preparing a delicious pasta dish, from classic Italian recipes to modern fusion flavors.
There are countless ways of defining power in organizations and its relationship to authority.
After all, we already use countless ways of discriminating rationally on the basis of the likelihood of future ability.
Most of us, mysteriously, have accepted its guiding hand, in countless ways of which we're largely unaware.
Your goal is to get Eric's report card out of the headmaster's safe, but there were countless ways of doing this.
The fifth of seven children, Mr. DeRubbio, a Brooklyn firefighter, was famous in the family for his countless ways of getting around the household rule against profanity and for the zany nicknames he gave out.
There are countless ways of mapping the tortuous course of music history in the 20th century, different methods of fixing its turning points and periods of maximum stylistic change, but a geographical approach is as revealing as any of them.
He's also given himself steampunk X-Men powers and thought of countless ways to launch hundreds of fireworks into the sky over his Stamford, Lincolnshire suburb.
Of all the countless ways to measure the health of the economy, one stands out as the most meaningful for American workers: Average real (i.e., accounting for inflation) weekly earnings.
GPU also sponsors youth athletic teams and contributes in countless ways to the fabric of the community, he added.
From spiked eggnog to shameless re-gifting to caroling "the Lord is come" to your neighbors the Feinbergs, the holidays provide countless ways to show people sides of ourselves we spend the rest of the year trying to hide.
A very un-Modern-like phrase appears in wall texts at the start of both the fourth and fifth floors, telling us "there are countless ways to explore the history of modern art and the museum's rich collection".
