How do I stop myself from getting too attached to people?

Being attached to someone is not a bad thing, if you learn to build a connection that is based on mutual respect and understanding.  There is a balance to building an attachment where both partners give and take equally.

The healthiest type of attachment is a secure one.  This begins with self- learning to be secure with yourself first before attaching to another person.  Otherwise, insecurities will be brought to the relationship.   

The best advice or answer to this question is to take your time getting to know a person and allowing them to get to know you.  Rush ordering a connection is often done to fulfill an insecurity or not experience feelings of loneliness. But, that is often a temporary fix and insecurity will often creep up later once the relationship is established. Neediness in a partner can often be seen as unattractive and then a negative cycle begins where one person starts to become distant, but the other person is often triggered into feelings of abandonment or insecurity.   However, if you take the time to love yourself and be comfortable in your own energy, that is often a good sign that you are ready to be in a relationship.  The healthiest relationship have a sense of autonomy outside of being together. 

Often times, when we rush into being in a relationship there is a need inside that wants immediate fulfillment and that often causes an overload of emotions and demands on our partner.  If you take your time to build, it will help you find a secure attachment within yourself and with the other person by getting to know one another on a deeper level without the act of neediness.

A big part of building a healthy relationship is being authentic.  This means, your words, actions, thoughts are in alignment.  For example, you genuinely are hanging out with someone because you have the same common interest and not just because you want to impress someone just to be in a relationship because you do not want to be alone.

There are other ways to build a healthy relationship beside taking your time.  This includes genuinely and actively listening to them and vice versa.  By fully taking the time to understand why you feel drawn to this connection can help you decipher if it is someone you want instead of something you need to feel secure.   Asking questions and sharing information about yourself and getting a bigger understanding of the person will help build a healthy foundation for a relationship.