The generals overthrew the government on Thursday after months of confrontation between the government of Prime Minister Yingluck Shinawatra and the royalist establishment.
Several hundred protesters gathered in front of a McDonald's in Bangkok's central business district, where soldiers with riot shields met them.
Chants of "aok bai" (go away) rang out loudly through the cheering and jeering crowd, as soldiers sternly looked on. Pushing and shoving broke out but there was no serious violence.
"I think this coup is so bad," said a woman who asked to be identified only as Urai to protect herself. "The government was good and Red Shirts are good. These soldiers are bad."
At the same time on Sunday, the military began meetings with the leaders of state and private commercial organisations, senior officials of the commerce, finance ministries and business leaders, Al Jazeera reported.
Officials from the Energy Ministry, oil trade and transport companies were due to meet military officers later in the day.
The army has also asked 18 newspaper bosses to a meeting on Sunday, presumably to receive directions on supportive coverage.
"From now on, the army will focus on solving the country's problems," a senior military official said on Saturday.
"The army would like to be in power for the shortest period they can. They want to make sure the country is really getting back to normal without any resistance."
Power now lies squarely in the hands of army chief General Prayuth Chan-ocha and his military government known as the National Council for Peace and Order, and their priorities appeared to be stamping out dissent and tending to the economy.