Creating test problems
Test problems have to be created by someone. UKLO is only possible because we share problems with ELCLO, the English Language Computational Linguistics Olympiad (which isn’t an olympiad, just a consortium of English-speaking problem creators). ELCLO is run by Drago Radev in the USA, and is most strongly linked to NACLO, the North American Olympiad.
If you’re a trained linguist (of any kind, whether a ‘linguistician’ or a polyglot or a language professional), you may turn out to be a brilliant problem creator, so why not try it? Look at some past problems and see if you can produce something similar. If you can, do share it with Dick Hudson, who chairs the UKLO test-creation team.
If you want some general guidance on creating problems, you’ll find an excellent survey of general principles here.