Communicate

Use most direct form of communication available.
Especially if many questions open, try to arrange a call instead.

E-Mails

same as clean code applies: a single, minimal purpose. structure cleanly without repetitions.

content:

• introduce by responding to previous email /events or introduce self (if first email).
• write short answer (actionable advice / help) which potentially resolves conversation.
• future steps / easy call to action

mirror:

• choose the same form of anrede/gruss like your conversation partner.
• adapt the tone / formality to your conversation partner.
• respond at similar times / at least working times.

respond within 24 hours or ensure the conversation partner receives a notice when a response can be expected.
get back to people if no response received in 72h.

Presentations

adapt length & depth to the audience. ensure the moment is right (if in doubt, ask).

make it look stunning. send drafts to target audience to involve them in specification.

most from https://productivityhub.org/2019/04/19/how-to-deliver-constructive-feedback-in-difficult-situations/