I was listening to Mark Manson (author of The Subtle Art of Not Giving a F*ck) on the Modern Wisdom podcast (great episode btw) and they were talking about how neediness comes though in energy, words, actions, and behaviors and how unattractive that is to women. Women have a very dialed in intuition and can detect neediness.
So when you jump into the dating world for whatever reason, don't be needy. Make sure you are grounded in what you want and be prepared to play the long, patient game. Don't get too excited about a match because it can go away as easy as it came, especially if you are deep down coming from a place of need.
Explore with yourself what you really want. Do you want physical intimacy or do you need it? Do you want companionship or do you need it? Do you want a long term partner or do you need it?
To want something you don't have but are willing to put in the time and effort - and be patient - you will find it. If you are chasing a need, it will keep running from you. Know the difference.
The best way to not be needy is to do the work on yourself that you know you need to do. Be the man you would want to date if you were the woman you are seeking. Be ready and show up as who you are and knowing what you want. Be willing to walk away when it's not right for you. Pick the top three things that are non-negotiable and negotiate the rest. Know what you definitely do not want and pass by those who display signs of that...those are your red flags. Don't waste your time projecting fantasy potential onto someone who doesn't meet your criteria. She's out there, know what you want and you will find her.