Single tickets are bought directly from the driver (it would be greatly appreciated if you were to have exact change to enact payment). A single ticket is valid for 2 hours from the time of purchase for all transfers and costs around €1.50/ €2.00 (in the summer season, from mid-June to mid-October).
If you plan to travel and explore the Maltese Islands extensively, the most cost-effective solution is the season tickets (long-term). They take the form of plastic cards and can be bought in almost every grocery/souvenir shop or at Malta Public Transport information points. There are 3 types to choose from: