What footwear and clothing do the Laws require?

Footwear (Appendix A.2). Players, umpires and markers must wear flat-soled ("heel-less") footwear when they play on the green or act as umpires or markers. World Bowls and Member National Authorities can approve specific colours for footwear and the types of sole.

Clothing (Appendix A.3). World Bowls and Member National Authorities can approve specific colours and types of clothing (including bowling gloves) for players, umpires and markers when they play on the green or act as umpires or markers. A competition's Conditions of Play must at least include footwear and clothing, including any sponsors' requirements (Appendix A.1.3.8).

Spectators (law 45). Spectators must stay outside the boundaries of the green and clear of the players, and must not disturb or advise the players. Betting or gambling on any game is not allowed within the grounds of any club.

Source: World Bowls, Laws of the Sport of Bowls Crystal Mark Fourth Edition, Appendix A and law 45, https://www.worldbowls.com/wp-content/uploads/2023/05/Laws_of_the_Sport_Fourth_Edition.pdf