Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Bangkok to Gaborone as you normally would.
Related info for your journey
Useful info, stats and facts about Bangkok to Gaborone flights.
Located just 11.1 km from the city centre, Gaborone Sir Seretse Khama is the airport most travellers will use when flying to Gaborone from Bangkok. Booking flights from Bangkok to Sir Seretse Khama (GBE) should be relatively easy as there are 0 daily inbound flights from Bangkok from 0 different airlines.
Bangkok Suvarnabhumi Airport is BKK and Gaborone Sir Seretse Khama Airport is GBE. These codes are created by the International Air Transport Association (IATA) and airlines use them to identify the departing and arrival airports in the flight routes they service. Bangkok Don Mueang Intl Airport (DMK), Rayong Utapao Rayong Pattaya Airport (UTP), Hua Hin Airport (HHQ) are some additional IATA codes for airports related to your trip.