The Election Commission (EC) on Saturday issued its list of dos and don'ts for election candidates, especially during the upcoming Songkran holidays.
EC secretary-general Sawang Boonmee urged prospective MPs to be mindful as advance voting registration winds up on Sunday.
Advance votes ahead of the May 14 general election may be cast from within a constituency, elsewhere in the country or overseas.
There will be a central advance-voting venue in each province, except in Bangkok where more than one such venue will be opened due to the higher number of eligible voters, Mr Sawang said.
He also cautioned cabinet ministers, political post-holders and state officials against using their positions and state resources to canvas for votes.
Cabinet members who are MP candidates or are seeking public office in the poll must take care to ensure what they say at campaign rallies is truthful, factual and accurate and that their speeches do not defame anyone.
The election laws also forbid live entertainment from being organised with the purpose of wooing votes. Parties should play their pre-recorded campaign song at rallies rather than have their MP candidates sing it to the audience.
During the Songkran holidays next week, parties and their candidates are free to join the festival although they must not sponsor or organise live entertainment or hand out free gifts to lure voters.
So far, the EC has received no election-related complaints, he said.
In past elections, most complaints were about vote-buying acts and state officials failing to behave impartially.
The EC is working with a network of state agencies and intelligence units as well as with private-sector groups such as the Internet Law Reform Dialogue (iLaw) and We Watch in conducting pre-election surveillance.
Mr Sawang added election ballots contain security codes which make it possible to trace the papers back to the polling stations where they were allocated.