"The CDA will mobilise every media outlet to explain the new constitution to voters," said public relations committee spokesman Sakchai Ounjitkul.
The budget is expected to be about Bt30 million, he said.
A referendum to approve or reject the new constitution is due to be held on August 19.
Publicity for the charter will include all television, cable and radio stations, websites, print media outlets, government agencies,
education institutions, billboards and places where crowds gather, he said.
For television and cable services, the CDA plans to air spot messages from 6am till 10pm with the theme of "Approve: New Constitution, close to the people".
The PR campaign is expected to reach about 12 million viewers.
A website run by the Parliament will be designated to promote awareness on the charter. It will have links to other Internet sites run by state agencies and education institutions.
The CDA will buy advertising space in major newspapers and its members will visit various newsrooms in a bid to boost news coverage about the charter.
Government agencies, including the Interior Ministry, will be asked to assist in disseminating information about charter provisions. All state-run schools and universities will get involved in the campaign.
Billboards will have a mascot logo of a green-light man. These will be put up at main roads and crowded places to encourage people to vote in the referendum.
CDA deputy chairman Seri Suwannapanont said the PR campaign was deemed necessary to overcome the opposition to the charter mounted by various anti-coup activists and the disbanded Thai Rak Thai Party.
Seri voiced concern that people opposed to the new charter had a large war chest to sway voters to vote 'No'.
CDA member Chirmsak Pinthong said ousted politicians might be willing to spend about Bt3 billion to defeat the referendum - as revenge against the junta.
Meanwhile, charter-writer Sodsri Satayatham said she was considering filing a libel suit against the September 19 Network against the Coup.
The network took out a full-page ad in Matichon newspaper attacking her for assuming so many positions at the same time and accusing her of being a puppet of the junta.
As well as being a charter-drafter, Sodsri is an election commissioner and member of the National Legislative Assembly.
PM's Office Minister Thirapat Serirangsan said yesterday he was confident the constitution would be approved in the referendum.
"It has some flaws but it is not so serious that it should be overturned. It has more good than bad points. I believe the public will not pay attention to small details," he said.