Seeking out the best colored pencils or watercolors, spending hours or even days painstakingly coloring a picture and taking photos of the finished work and either posting them on Facebook or entering them in some coloring contest.
That's what thousands of Vietnamese grown-ups are busy doing these days.
Unusual as it may seem, coloring is now no longer limited to kids and artists since several adult coloring books were published last month.
Over the past month four of them have been among the top 10 bestsellers, with two of them in first and second places this week, according to Tiki, one of Vietnam’s major online book retailers.
They are also dominating the rankings put out by Vinabook, another huge retailer.
Tran Phuong Thao, deputy CEO of the Hanoi-based Thai Ha Books, said the combined sales of "Secret Garden" and "Enchanted Forest", both by British illustrator Johanna Basford, have hit 40,000 copies.
The figures may be next to nothing compared to the books' world sales -- more than 1.7 million -- but in Vietnam, where any title that can sell 15,000 copies is deemed a major success, they are a huge hit.
A coloring contest organized by Thai Ha has attracted nearly 1,000 entries in three weeks.
A similar competition by Nha Nam, which published two other bestsellers -- "Animal Kingdom" by Briton Millie Marotta, and "Beautiful Day" by Korean Park Young Mi -- has also garnered huge attention.
More than 1,000 works have been posted on the event's Facebook page, on which 4,500 others said they would join.
While the age range of the books' readership is unclear, Thao said the oldest competitor in Thai Ha's coloring contest is 45 and the youngest, three.
Thao said coloring books help people forget other pressures.
In fact, since they first came out in 2012, adult coloring books have been praised by therapists around the world for being a flexible and cheap stress buster.
"Many friends tease me for coloring, saying I'm childish, but I do not feel so," Nguyen Thi Minh Nhut, a reader from Ho Chi Minh City, wrote in her review about "Animal Kingdom" on Tiki's website.
“I can spend 30 minutes a day doing it to get away from life's pressures.”