This is how I approach it. A "weird" chord often substitues for a simpler one. Basically, chords have a postion in a "progression" that is like family members. The chords relate in specific ways to each other. Find out what the basic chord progression is. The weird chord often relates to the basic progression and is a substitute.

Ya' gotta' find out what the composer, arranger or player means by the chord. Maybe it's just a weird uncle with gold sunglasses and a rakish hat. Or a grandfather in gym shorts.

I don't believe there are any weird chords. Just embellished ones. How to use them? Study basic harmony. Junior colleges offer basic musicianship courses. If you are into jazz, there are some basic books that help. I recommend the Dick Grove mail order series. When you study jazz guitar a world of chords open up.

Frank