1. First off, create a Google account that you can hand over to your web team when you’re done. The tags you create will be linked to that account (so don’t use your personal account, m’kay?).
2. Use Google Maps’ Local Business Centre (LBC) to create the map tags.
3. Start simple, with just the basic info for each tag you create. I made the mistake of writing complex descriptions for each tag and these had words in them that Google didn’t like – they got ‘flagged’ as ‘waiting for content check’. Here’s an explanation of what to do if this happens to you. To avoid this happening at all, don’t write a description to start off with. Add it later, once the tag goes ‘Active’.
4. Add any pics and vids later too.
5. Next, Google needs to verify you are who you claim to be. To do this, you can opt for: a phone call where they ask you to key in a PIN they give you; an SMS text message PIN to a mobile phone; something that uses the postal service (I didn’t try this)
6. If you go for the phone call option, make sure that you’re near your reception/call centre switchboard to help your receptionist key in the PIN.
7. You can do the SMS thing quite easily though, with a little workaround. Here’s what I did for three out of four of our teaching centres. I used my personal mobile number. Got a text message with a PIN in it. Entered the PIN myself. Then once the tag turned to ‘Active’, I edited the tag’s info and deleted my mobile number. Ok, yeah right… Now that seems like a big hole in Google’s security, but hey, it worked for me, and it saved me a lot of time too.  [edit 6 Oct 09 - Our WebAdmin tells me that this doesn't work anymore. It appears that Google has now spotted this loophole and fixed it. ]
8. Once all your tags are ‘Active’, go back and edit them to add descriptions and stuff.
9. the first photo you add will be the one that appears in the listing, so add the best one first. See post on this.
10. If you add video, it seems to block any images from appearing in the listing. So if you want your tag to appear in the search list with a nice pic, don’t add a video to your tag. I could be very wrong here, but this is what happened to me. Any tips for fixing this, are most welcome.

In my limited experience, the whole Google Map tag creation thing seems a bit clunky. Not very slick. Too many workarounds and uncertainties. But I got it to work OK in the end.

[edit 24 March - here's an instructional video from Google, nice... but no help in avoiding the bugs. Recently 3 out of 4 of my listings on Google Maps have vanished from the Map, although they're still in the Local Business Centre lising. I'm growing to hate Google Maps. Shame really, because it's cool when it works. It's just that it doesn't seem to work very well most of the time, which is very uncool.]