This is a subject I have long given thought and many articles exist on this very top all over, do check them out and consider some of these points as well.
AoA
The first award many people receive is an Award of Arms. This is basically a "we miss your presence when your not there" award. This is when a person contributes so much to our society that we miss them when they are not there.
Note: "contribute" does not mean this is a service award. I seriously do not believe that a person has to be justified as providing any formal service to be acceptable. Contributing is more like being a participant rather than having a more passive role. They may dance, they may participate at fight practice, they might help set up stuff, they might merchant, they might create beautiful things, or provide games for children to play, write articles for the local newsletter or pretty much anything that contributes over all to our general enjoyment in the SCA.
Specific Awards...
This is to say, fighting, archery, A&S and so on, basically specific fields of play and interest in the SCA.
When you write, try to focus on why you think they should be recognized for that particular award. A person may be a really wonderful and dedicated fencer but if an award is prowess based, then being a great teacher might not be enough or even related. A person could make the most tasty and phenomenal wines, but if they are not using a period basis for them, there might not be any award to recognize them with.
There are all sorts of wonderful websites that describe awards, also don't forget to check with your local group for any more local awards that may be given out.
When in doubt, provide more, not less.
While it might read off as silly to get all sorts of unrelated info, you would be surprised of what comes in handy and where.
Sometimes people may not know who the person is, be it a polling order or even the scribe. Links, pictures and descriptions of the candidate for an award would not be unhelpful. Occasionally a name is mixed up or really useful details are forgotten, sometimes the correct details and other information can be linked together with enough information.
Also, don't forget the scribes, the person who may finally end up creating a scroll for the receiver of the award may not know them at all. That extra information can really help create a more personalized award scroll.
Words of Wisdom-ish?
I have heard all sorts of wild and crazy stories about awards in the SCA, some amusing and some not much so, but what you have to remember is that awards were created to reward and encourage people, not the opposite. There are many different types of awards and they seem to be coming out with more all the time, this is because people want to see people recognized. Do not fret if your friend does not get a certain award, it could simply be they are either not ready, or not known or seen enough or whatever.
Pollings: many awards go through a polling process. This is where members advise, not to be mistaken for voting, though I'm sure that happens as well. Because of this, many people are going to have varying ideas and advice accordingly and I will say one thing, I dislike advising against/not-advising for people, I take no joy in it at all, however I also keep in mind how sucky it would be for the a recipient to find out they got recognition just because people liked them but not for anything they accomplished. What we want to do is recognize people for all the right reasons and while it might not always happen (I don't know this, just open to the possibility), it's always best to try.