I have been reading your postings (in women seeking men) off and on for 3 months. Here are a few tips you can take or leave...
1. If you're BBW, admit it. Don't say I've got a few excess pounds but "I'm working them off...". It sounds juvenile, and suggests we should get used to hearing you say it.
2. If you're looking for a trophy either physically or economically, admit that too (and you might as well be specific). If I'm being interviewed as a potential meal-ticket, I'd like to know in advance.
3. Don't apologize or act sarcastic because you're posting in CL; if you want to post, do it and don't act like you're less desperate or more savvy than all the rest.
4. If you've got an upper limit on age, make it vague; I know women who are in their 50's who make most 20-something hotties look drab and dull. The same is true of men, probably more so.
5. Include a recent picture and make sure you're smiling. On a personals website, a picture is worth alot more than the usual 1000 words.
Now here's the lecture: About 75% of you have these detailed lists of preconceptions you require "us" to meet in order to be worthy of an audience with you. Some of the most common ones are: LTR, honest, "not a game player", loyal, sensitive, "like to cuddle in front of the fireplace", willing to be nice to your pets, and most of all, eternally grateful that YOU decided we measured up to your standards.
I have news for you: with the exception of a few harsh physical or economic realities (see items 1-5), you don't really know who or what you're going to be attracted to until you make eye-contact, have a conversation, and see how it feels just to be in the same space with that other person. We all have a story we're telling ourselves about who we are; then there's the person the rest of the world sees, and more often than not they don't match up as well as we'd like to think.
Keep it simple, keep your minds open and your legs closed (initially at least) and you might be pleasantly surprised at what you find.