Be all things for all people. If you claim to like every type of music, sports, body types and personalities you may be stating that you have no distinguishing interests. Tell what makes you different, not the same as everyone else. You are not trying to attract everyone that reads your profile. You are trying to eliminate people that do not fit your needs.
Proof read, spell and grammar check your profile. Also have several friends review the finished profile. Write in complete sentences. Write complete words. Write “please” not “plz“. Sloppy writing makes a negative first impression like a dirty car. If you prefer a casual writing style make sure that it communicates clearly with warmth and lots of personality. Don't make the mistake of appearing sloppy, lazy or even ignorant.
Make claims that are credible. Don't say that you are smart or funny or athletic. Instead tell a good story to show how this is true.
Avoid meaningless cliches. Declaring that you like to “live life to the fullest” it is just too vague. That statement can easily mean different things to different people. Instead illustrate your statement by describing a story about a favorite hobby or vacation.
Don't be too brief. You must include enough information to offer a sufficient peek into your world. If you are too brief you may not distinguish yourself enough to stand out from the crowd. A long profile will quickly filter out those that would not have been interested anyway but give the interested dating service members enough information to decide to contact you and not some else. The advertising industry has proven this in definitive tests for over 100 years. Well written, informative, long copy is necessary and always outsells short copy.
Be bold but diplomatic about expressing your personal preferences. If you prefer dates from a certain race religion, age or body type there is nothing wrong with that. However express it clearly as your personal preference only and not as a negative about the other excluded types.
Don't be too narrow when specifying the characteristics of your ideal candidate. A long laundry list of inflexible, narrow partner preferences might just scare away good candidates.
Use humor. It shows that you are clever, smart, fun and down to earth in ways that a direct claim will not work. It also makes you seem more approachable. Don't use humor at others expense. Don't use off color humor. Don't use too much self deprecating humor. This can be misinterpreted as a lack of self confidence. Don't worry about making everyone laugh because you will always confuse and even turn off some. The people that get a kick out of your specific brand of humor will most likely be fun to be around