wow! sis aquacharly, saw your crystal collection sa FB. ang gaganda pala pag madami at sama sama. parang candies! 
Hahaha. I try to keep it all simple and flexible. Napansin ko kasi -- the collectors do not mix crystals in a bracelet/necklace; just add a gold/silver accent or another crystal that acts as a "kicker" or "cleanser".
For example, If I have a meeting for tough negotiations, I wear my purple amethyst, onyx, and citrine bracelets - for mental open-ness, protection versus evil intent (lol) & energy. I gotta keep all still on a workable level hindi yung overpower the other party, or baka ma down sila sobra: no deal ang ending, hopia!
If it's gonna be a staff technical meeting, I replace the onyx with a blue lace bangle -- for patience &
empathy. Lol, uli.
When I travel, I use bracelets of tourquoise, jade, multi-colored tourmalines & citrine - for safety --
sometimes, garnets are required (pag tense ako, ewan why) for energy and alertness to both danger and good things.
When I feel I am gonna be on an anger roll -- blue lace, rose quartz, clear quartz, and moldavite.
The 1st 2 bracelets calm me down, the clear quartz helps to float clear thinking over emotions, and moldavite -- it's a kicker (ups the energies of the other crystal bracelets)
When I feel like Suri Cruise -- needing more love than usual -- hahaha... It's the green and purple amethyst bracelets, & a rhodochrosite bracelet. Pag more pa needed -- lol, pile on the moldavite & ruby bracelets. Yeah, I jangle a lot, lol.
Madami pa combinations, depende sa feel ko for the day.
There are days I don't wear any, coz my balance is fine ( or Advil kicked in, lol).
There are days I wear 4 bracelets of 1 crystal - bad sign yan per my sec. Lol
Basta I can't take more than 1 bracelet on me of ametrine, citrine or bronzite (too strong).
I can't wear bronzite with other protective crystals -- overkill na.
I don't wear malachite -- but I have a small block in my bathroom.
When I fear a place or just feel shivery all over/threatened by what, I don't know, -- I use sabay sabay bracelets of onyx, black tourmaline, jet & moldavite.
Going to hospitals, wakes, busy places like 168/Marker!Market!/Congress lol. -- I always use my onyx bracelet with lapiz lazuli plus whatever else feel ko I need.
Where you want to keep your 3rd eye closed -- do not use amethyst, clear quartz, rose quartz.
OT - I get feeling drained as in dead after shopping at SM Makati -- that area on the 2ndFlr or 3rd floor corner area across National Bookstore or the hotel. Has anyone here experienced this? Creepy, so I don't go there anymore.
When I feel the need for extra suerte energy or am into complicated work -- I use a bracelet of ruilated quartz with gold threads & another of ametrine.
When I feel sad, I wear sangkaterbang aquamarines with onyx -- I have a beautiful pair of long necklaces with big stones of both crystals, as well as a vintage Cartier jewelry set of both from my dear lola.
Sa family daily dining -- dati doon mainit ulo namin ni hubby. We take Office and business calls there; I talk to my house staff there. Very bad for family relations - tense. I put a 7inch triangular block of
rose quartz on the buffet able, and wound around it a necklace of carnellan chips. The rose quartz fosters positive emotions, but it also feels "heavy" when it has absorbed too much negative vibes. SO the carnellian on it cleanses it continuously. But when I have 5minutes to spare -- I put that rose quartz under the kitchen faucet's running water to cleanse it. Before I put it back on the buffet, I do my programming.

. Works ok. Now my dialogue to house help guilty of whatever: "that's your job" (in English ha, lol getz nila agad). Or: "pagod ka? Mag-snack ka uli, at isipin mo again.". Bow. Lol