The anger gave way to a lighter atmosphere on Monday as riot police retreated, leaving huge masses of protesters in control of at least four major thoroughfares around the city.
But although there were few police on the scene, some protesters feared a repeat of Sunday's clashes, donning goggles and masks to protect themselves against tear gas.
"We can't relax too much," graphic designer Felix Kan told AFP. "This is still China -- you never know what could happen."
The festival atmosphere was tempered early Tuesday as protesters attempted to second guess what the next police move would be, an AFP reporter at the scene said.
Organisers also announced to the crowds that water and food supply stations had been targeted in attacks at some of the protest sites, but appealed for calm.
In Mongkok, a busy shopping hub, police were called after a car drove at high speed past crowds of protesters, though no one was reported injured.
The demonstrators are furious over last month's announcement by Beijing that while it will allow the city's next leader to be elected in 2017, it will insist on vetting the candidates, with critics branding the move a "fake democracy".
Public anger over rampant inequality is also at its highest in years in a city once renowned for its stability.
- 'Umbrella revolution' -
Cantonese pop music filled the air during the second day of what some are dubbing the "umbrella revolution", as protesters have been using the canopies as shields against tear gas and the scorching sun alike.
One British sympathiser won huge cheers as he set up a barbecue and began handing out hamburgers and sausages to the protesters.
"I saw everybody was just standing around and just eating bread and bananas and I thought, 'These guys have been here for 24 hours now, and everybody needs cooked food'," Daniel Shepherd, a finance broker by day, told AFP.
"Firing tear gas at students that are unarmed, I think, seems a bit excessive," added the 32-year-old.
The crowds hoisted up a makeshift copy of the "goddess of democracy" statue that graced the 1989 protests in Beijing's Tiananmen Square, while lamp posts were adorned with yellow ribbons -- which, like the umbrella, have become a symbol of the movement.
But many Hong Kongers expressed frustration at the huge disruption the protests have caused, with the crowds blocking key junctions in the busy Causeway Bay and Mongkok shopping districts as well as the biggest protest site in Admiralty.
There was chaos on the transport network, shuttering many businesses, with schools in two central districts set to close for a second day on Tuesday.
Some social workers and teachers also went on strike after the Hong Kong Confederation of Trade Unions (HKCTU) and the Professional Teachers' Union (PTU)called for members to take action, the South China Morning Post reported.
- Political headache for China -
Analysts say the protests put the Chinese government in an extremely difficult position.
Communist authorities are worried that dealing with the protests too softly could encourage wider protests for greater freedoms on the mainland. But a heavy-handed response could spark an international outcry.
"It has the potential to be such a major crisis," said Christopher Hughes, a China expert at the London School of Economics.
He warned to AFP that Hong Kong could see a repeat of China's violent crackdown on the Tiananmen Square protests.
"If they did decide to send in the tanks, who could stop them?" he asked.
"They did it in 1989 and got away with it and they're a lot more powerful now. There would be some negative impact, some business confidence, but how long will that last?"
The United States urged Hong Kong's leaders to "exercise restraint".
Former colonial power Britain also expressed concern, calling for "constructive" talks to end the standoff.
Beijing moved swiftly to wipe mentions of the protests from Chinese social media -- blocking photo-sharing service Instagram altogether -- and reiterated its hardline stance, opposing the demonstrators' "illegal" actions.
Hong Kong's police force defended the use of tear gas, with Assistant Commissioner Cheung Tak-keung saying officers had no other option when "police cordon lines were heavily charged by some protesters".
The mass protests came after a week of increasingly tense student-led demonstrations that saw people mob the city's leader and storm the central government complex.