Train until opportunity looks familiar.

Opportunity usually arrives with less warning than you would like, and the response has to be immediate. Training beforehand changes what that moment feels like, from an emergency you are unprepared for to a situation you have rehearsed in some form. Familiarity is the entire benefit.

Work out what the opportunity you want would demand of you, and practise that now, without it. When it comes, you want to recognise it rather than scramble.