Thanks to Marius Hobbhahn for the inspiration with this comment and to Stefan Schubert for motivating me to write about it on the forum!

tl;dr: Create a website, an Airtable, a Slack channel, a Google Drive, and even create coordination orgs so that new EA organizations have the resources to avoid wasting time and effort with "rookie mistakes".

The current situation.

The number of EA-aligned organizations has rapidly grown in the past few years. Charity Entrepreneurship alone is helping to establish about five new EA-aligned organizations per year. And I am sure there are many more EA orgs that I don’t even know about, because every time I attend an EA Global I end up knowing about a handful of new organizations and projects that I was unaware of. Many of these organizations are small passion projects initiated by a couple of individuals, and there are some of these that could potentially be scaled up into bigger and more successful organizations. 

My experience from attending the Meta Charity Roundtable at EAGxPrague is that there is a common sentiment among new founders of lack of guidance, lack of networking, and trial-and-error. As a founder of one of these small new organizations, I think this is a good point in time to put together efforts from EA organizations in order to learn from each other’s mistakes and successes, so that we avoid making "rookie mistakes".

Some concrete issues.

When creating our organization, I relied a lot on the EA Groups Resource Centre website, even though this is meant for in-person groups, like university or city groups. This website by Global Challenges Project is also useful. But I think we also need a similar website for outlining a common strategy among EA organizations. For example, some of the key questions I had when creating our organization were:

• Should we aim for the EA movement to be “wider” (more people who are less engaged on average) or “taller” (fewer people who are overall much more engaged)? How should this shape our priorities for how we set up organizations?
• What should our EA-aligned websites look like, in terms of design, structure, and aesthetics?
• Should we use the "Effective Altruism" name in our organization description, or should we describe our organization without using the words Effective Altruism? What are the dangers involved in using the EA name?
• Are we allowed to cover topics beyond the EA core areas if we want to achieve funding from the EA Infrastructure Fund or a similar source?
• Should we set up our organizations as charities, NGOs, foundations, associations, or something else? (This might vary from country to country)
• What is the best strategy for ads?
• What should our social media strategy be?

I had to learn many of these things over the past six months, from over fifty 1-on-1 meetings at several EA Globals. I am extremely thankful to a number of people for their feedback, and I ended up making many friends and contacts in the process. 

However, I do feel like I wasted several weeks to months of my life and filled some funding applications wrong because I initially had the wrong answer to most of these questions. I think many people might be in a similar situation now and in the near future, particularly as the EA movement grows.

A note on EA-center and EA-periphery.

I think EA still suffers from strong founder effects from being created in particular cities in English-speaking countries. EAs in the Oxford-Cambridge-London area and in the San Francisco area live in a very privileged place in terms of access to the EA movement, and many might not be aware of the difficulties of being an EA outside of these circles.

As an illustrative example, I was an EA living in Latin America from 2015 to 2019. In these four years, I think I had the experience of meeting about 3 other EAs, usually when they came over to give a talk. For comparison, after moving to Europe I had the chance to talk to over 100 EAs in the last year alone.

For these reasons, I think the current word-of-mouth system presents severe limits when the movement is now growing outside of the Anglosphere, and might prove unsustainable.  There are many EA organizations growing in continental Europe, and I'm aware of some in Asia and Africa. The way this is currently set up, many people, particularly those outside the two English circles (Oxford-Cambridge-London and San Francisco) need to use trial and error to create their organizations and then attend an EA Global (usually traveling far) to get feedback. 

This is not a smooth experience. More established EA organizations could give us a greater clue on how to act by setting up some online systems now instead of later.

Some concrete suggestions.

1. As mentioned above, I think we need a website similar to EA Groups but for EA organizations that are just getting started.
2. There might be over 500 EA organizations at this point. I think we need a directory (e.g. an Airtable) to keep track of all currently existing EA and EA-aligned organizations. Michael Aird created one for longtermism/x-risk some time ago, but it might now be outdated, and there’s no simple form so that we can add ourselves to this table. Also, many other EA orgs work on areas outside of longtermism. I think this new table I'm suggesting could be managed by the Centre for Effective Altruism or a similar organization. Hopefully this table wouldn’t require a lot of time to update. But even if it did, it could be worth it in terms of networking opportunities and awareness of what organizations already exist so that we don't multiply our efforts unnecessarily.
3. We should have a Slack channel for “EA Organizations” to share insights, exchange information, network, organize meetups, etc. The EA Groups Slack channel is useful, but it’s focused on organizers for local or university groups, not organizations.
4. We could use a shared Google Drive with useful materials, particularly in terms of strategy (e.g. how to approach people outside of EA, how to do social media outreach). These documents should have reasoning transparency for why we are choosing particular choices as our strategy so that we are not just applying strategy chosen by established organizations blindly, but so that we can question it and pivot in case the epistemic/funding/talent situation changes.
5. As David Nash has recently pointed out, organizations focused on coordination are either non-existent or lagging behind research-focused or career-focused ones. There seems to be space for more organizations that focus on helping others with infrastructure, networking, coordination, etc.

I hope that some established EA organization takes up this initiative. I also hope to hear more suggestions in the comments and that this inspires some work towards a more international and inclusive EA community!