Tips for writing advocacy messages
This quote from a debian-devel-announce post captures quite well the gist of advocating people:
When you advocate a person, you are saying that they need and should get unsupervised upload rights on the entire archive, right now. In the past some people were advocated who at the time had not yet done any Debian related work. Please only advocate people who have contributed to Debian already, don't advocate someone that you expect will get involved in Debian later on. Having to cancel an application, or having someone disappear while in the NM process, is a waste of time and motivation for everyone involved. As such, we prefer that people who want to apply to NM have been active in Debian for a while already, and have built up some experience. In the last few months, we've already redirected some people to the DM process when we felt that they were not ready to become a DD yet, and we will continue to do so. Please consider this an official policy as of now.
Now, this does not mean that an advocacy message should be a cumbersome, long and convincing thing that takes a day to write. It's more to do with what is written on it.
The bottom line
This is an example of a perfectly good advocacy message that can be written in less than a minute:
I have personally worked with NAME <EMAIL> <GPG KEY FINGERPRINT> for a sufficiently long time and I know NAME can be trusted to have full, unsupervised, unrestricted upload to the archive right now.
Advocates who are desperately short of time can even reuse that bit and fill in the blanks: we really don't mind as long as they mean it, sign it and put their reputation behind it.
There seem to be some problems to process inline signed mails, so it's best to send pgp/mime mails.
Tips for making it better
Extra details really do help: they might help FD in making a better choice of AM, or they might help the AM in seeing the existing Debian activity and make the process faster.
Show the work of the applicant
Anything that can be seen does not need to be asked, and as the advocate you are likely the person in Debian who is in the best position for providing pointers to what can be seen.
Rule of thumb: if you're writing something that shows the work of the applicant, you're doing a good job.
Multiple advocates are always appreciated: if you work on projects A and B, please get an advocate from A and one from B, instead of asking someone from A to also go and dig details about your work on B.
Skip the rituals
Skip the rituals. NM is not a university exam or a job interview: there is no dress code and no need of flowery words or fancy letterheads.
If you're writing something that sounds a waste of time, skip it: it very likely is a waste of time.
NM/DM: make sure you advocate for the right thing
If the applicant is not a DM yet, please also add a line about why they haven't been advocated as DM before.
This is because it sometimes happens that people get advocated for NM when the intention is to advocate them for DM.
Still quoting from that debian-devel-announce post:
Common sense is more effective than you'd imagine.