Getting started
What to have ready before you start
A support conversation is mostly a search for context. The fewer round trips that takes, the faster the answer.
Have the reference number
Whatever identifies your transaction — an order number, a booking reference, the email address used at the time. This is almost always the first thing asked for, and having it ready removes an entire exchange from the start of the conversation.
Say what you have already tried
If you have cleared a cache, reinstalled something, waited a day or contacted someone else, say so in the first message. Support staff otherwise have to suggest those steps in order, and that is three messages spent on things you have already done.
Describe the symptom, not the diagnosis
"The button does nothing when I click it" is more useful than "I think it is a JavaScript error". The second may be right, but the first cannot be wrong, and it points at the same place.
Attach a screenshot if you can
One screenshot usually replaces four messages of description. If the chat channel supports attachments, use it. If it does not, describe what is on screen in the order it appears.
A short message is not a rude message
Support staff read hundreds of conversations a day. A message that gets straight to the point is easier to help with than one that apologises for three paragraphs first.