When someone experiences a break up in their relationship they can sometimes use an aggressive way to get their ex back. This aggressive action is the one that most think of but is actually dangerous to use unless you make the right moves. This method does not mean chasing after your ex begging or pleading for them to take you back, it is something altogether different.
The aggressive approach you must take is to know where your ex hangs out and making sure they see you often. You need to act like you are confident and have been doing great without them in your life. If you appear as if you could take them or leave them that would be much better. You must be nice and courteous at all times when around your ex, but make sure they are aware that you have made it a point to talk to them but you are not hung up on them.
Another approach is more conservative. You can still run into them while out, but do not be so aggressive with them. This method can take longer to work and you may find that you become friends with your ex in the long term. If you talk to them, you can let them know that you still think about them and feel there is still a connection. You don't need to go out of your way to talk to them, let it happen naturally. Be honest with your feelings without going overboard with it. Your hope is that your ex will start to have a change of heart and start to contact you.