As an equestrian portrait photographer, I keep this blingy gray duffle bag that I won as an All Around Champion award in my trunk at all times. I don't go to a [local] session without it! Although, sometimes I'm forced to consolidate the contents and only bring the absolute necessities for when I travel by airplane. First, I gotta say, I LOVE when I'm able to use an award that I won from showing. I won this thing 10 years ago and it's in constant use!
I keep this with me not for every single client to use it's contents, but in case they forget something! In fact, I tell my client to pack themselves almost everything that I have in my shoot day bag. But sometimes they run out or maybe forget their entire bag at home? (yes this has happened!)
Now on to the good stuff. What the heck is even in here?!
a black nylon halter & black lead rope
first aid kit
rags
lint roller
fly spray
ear fly protectant
bug spray (for humans)
face glo, baby oil, pam (all can be used as a face shine)
static guard (for hair & clothes)
hair spray
dry shampoo
hair ties & bobby pins
hair finishing stick (for flyaways)
oil absorbing sheets (for sweaty faces!)
HotHands
lotion
double sided tape
Tide to go pen
tweezers
mini clippers
dental floss
feminine hygiene products
Some other stuff I keep in my trunk at all times that I use for getting ears up:
stick horse
broom
umbrella
grain bucket
mirror
pompoms
When I travel to a session by plane, I only include the absolute necessities specific to the sessions (so it can vary!). For ears, I mainly use various random things around my client's barn like grain buckets, sticks, brooms, empty grain bags, etc. as well as the AllEars app.