Part 1: Lifetime relationship (seeking a wife)
Your photo. Your latest snapshot in a suit from the office neither your semi-naked body planted into sand on a beach will not do best work for you here, assuming that you are looking for a lifelong relationship. The best approach is to present yourself in a quiet, homey background, in armchair, with a grey Chihuahua sitting on your lap. If you got no pets, just borrow one for occasion, or post a close-shot of your face with your best smile. Note, even your very best picture with past girlfriend sitting on your lap, will not be a good substitute for a pet picture.
Your text. It is not a good idea to write something like: I am tired from all work and no play, I need you! or, just plain Hey girls, I am here! Dont take me literally, please, all I want to say is that telling her that you are tired workaholic (or tired womanizer) and that is why you are here, will not do any good. Better is to give her brief and to the point description of your main character features, your interests in life and plans. Leave the rest for future chats.
Temptation. This depends on what kind of woman you are looking for. Tune her on your wavelength with such phrases, for example, as I will take you, my love, to Paris, and we will spend a week at Louvre. Or, My dream is to awake every morning and hear cheerful giggling of our kids. Or, one more: I cant imagine my life without forest trail and a backpack. These points are needed to give woman an idea on what will be her life with you. If you are seeking a music lover, do not write modestly I love music. Better write something like: I have got blown away by the recent concert of Santana, or Requiem of Mozart makes me cry.
Part 2: A brief romance (just some good time)
Photo Feel free to post your naked torso, of course, if you have one to show. Or show yourself behind the wheel of a red Corvette. If you still driving this Ford Escort 89, then better show her a huge bouquet of flowers in your hands, or just your best smile. In other words, give her a hint that you are light, funny, kind, not intending to load her with your problems and capable to give her few weeks of a good time person.
Words You are not looking for a wife, so she should not hear about the depths of your personal life. However, by all means you should not tell her that you are merely seeking a partner for intimacy. She would not like that. Women tend to seek some degree of real emotion in any relationship, even in a very short-lived one, where men could see nothing, but mere a physical thing.
Bait. It is a call for romance, so you have to be romantic. Promise (and give her) beautiful sunsets by the ocean and coffee in bed in the morning, good time without pledges and mutual obligations, and she will be OK with the rest. There will be no immaterialized promises, no hard feelings or broken hearts, so when the time will come, you will depart graciously from this romance and you both will move on to the next one.
Good luck.