Whether you have been hurt in the past and wish to avoid being hurt in the future, or if you just wish to have a fling without strings, there are many ways you can remain emotionally attached in any relationship.
Keep your personal stuff to yourself. It can be easier to remain emotionally unattached when you keep your deepest thoughts and goals to yourself.
Ask light and easy questions when talking to those with whom you wish to remain emotionally unattached. Talk about the weather, their last shopping trip, favorite movies and things that have nothing to do with emotions or personal issues.
Remain aloof and emotionally unattached by staying busy. When you busy yourself with work, exercise and lonely activities, you can remain emotionally unattached with little trouble.
Stay away from those who turn on an emotional response. Whether it your sister who always asks for advice about her crumbling life and never takes any that you offer, or a co-worker who wants to unload all of his problems on you, the best way to remain emotionally unattached is to steer clear of these people as much as possible.
Give your information out to those you want to mingle with socially, but don't get their information. You can remain detached by allowing him to call if he wants and if he doesn't then you can keep living your life without him.
Go out with different people all the time, instead of choosing to go out with only a small group. The less time you spend with one or two people, the easier it is to remain unattached emotionally.