Every venue coordinator has a short mental list of planners they recommend. It is short because it is built on trust rather than marketing, and being on it is worth more than any advertising you could buy.

Go and meet them, before you need them

Ask for twenty minutes and a look around. Do not pitch. Ask what they wish planners did differently, and then listen, because you will get an honest and specific answer that almost nobody else has bothered to ask for.

Make their job easier

A venue is not judging your taste. They are judging whether you will be a problem: whether you will run over on bump-out, whether your suppliers will damage something, whether they will spend the evening answering questions your run sheet should have covered.

Send the run sheet in advance. Confirm access times in writing. Leave the room the way the contract says. Do that twice and you are on the list.

Read the venue contract properly

Access hours, what is included, what is charged as an extra, the noise curfew, the pack-down deadline, and who pays for damage. These are the terms that cost money later, and most planners skim them once and discover them on the day.

The relationship goes both ways

Recommend venues to clients when they genuinely fit. Send a thank-you after an event that went well. Tell them when a supplier of theirs was excellent, because they hear complaints far more often than compliments.

None of this is networking in the uncomfortable sense. It is being straightforward and easy to work with, repeatedly, in an industry where a lot of people are neither.