Well as far as storage goes-
Whenever i have stored lsd its been in some foil, in a wooden box in a dark room temp sort of area.
They shouldnt degrade too hard there, i wouldnt leave tabs more than 3-4 months though to be safe.
In saying that though the tabs you buy could alread be a year or more old xD
As for shrooms im unsure, i havent had them much my storage was just a plastic saddy bag in a box.
And for a trip ritual type thing, well i cant really say because i dont know you.
But when i trip i do lots of art, listen to music, ponder life and revelations and enjoy nature.
Also an anxious trip sitter can be a problem, you'll find yourself getting anxious about why they are anxious.
Although i could be wrong, if its your girlfriend just do some research on how to trip sit and talk her through it before the trip.
Just be careful when tripping anywhere other than home, you dont want to get hurt or lost in the forest tripping trust me. Your motor skills and rational thinking will be hindered greatly!
Its kinda hard for me to sum all of this up
so i'll end this comment with do some research on how to first time trip and what to do etc, it'll make things a lot easier to understand when the time comes!