If you know that -ify is used to change a noun or adjective to a verb, particularly with the meaning “to make noun/adjective”, you can make connections between, say, diverse and diversify, or beauty and beautify. You can use this practice to even break down what is considered to be the longest word in the English language, ‘antidisestablishmentarianism’.
One of the best ways to expand your vocabulary is by observing words in their natural habitat, that is, reading, listening or viewing them in context. Reading is typically the most useful: because you will be more likely to have to reproduce words in written form, being able to visualise the spelling and grammatical context of the word is beneficial.