The only real answer is, you don’t. You can go on dates with different girls and then ignore them and hope they will go out with you again when the whim strikes you. But you will never build a track record or find a girlfriend with this technique.
You will just have a series of hookups that lead to nowhere. If you do find one who sticks for a while, you won’t have the skills, focus or dedication to keep her happy for very long.
If you are trying to have relationships with all of them, then you are in for some trouble. You will fall in love with several of them. Several of them will fall in love with you — and not necessarily the same ones that you love. You will end up lying, cheating and deceiving all of them, and you will probably end up with no one.
You can go to the dog pound and adopt seven dogs. But you can really only take care of one dog, so you decide you will feed one of them every day. None of the dogs will be happy. None of them will grow to love you. You are just generating misery and dysfunction, and they will probably all run away.
There may be a time when you are interested in two girls and want to get know both of them. A date is not a commitment, so it’s fine to take them each to dinner, take one grocery shopping with you, and go watch her son’s little league game with the other.
You need to let them know that you are not going to be ready to enter into a relationship for a few weeks, that you are seeing other people, and that you want to find out if there is the potential for more with her. If you become sexually active with one of them, it’s time to make a decision and pick one.