Right now i don't want to seem counter productive or bitchy here.....But questions like this just clog up this forum!
They are everywhere!
"I open then don't know what to say..."
"My conversation gets boring...."
"I run out of things to say..."
Are you new to the Game? If you are i would suggest reading more into the Mystery Method and learning the basic principles behind that..
After the open is A2, This is when you get the Female -> Male Interest, Basically here you DHV yourself so you use Stories, Gambits, Negs etc.
When i was new to the game i got some canned material and used that when i ran out of things to say. I suggest doing the same. Or making up some DHV stories so that you know evan when you run out of things to say you can start to tell one of these stories.
http://www.venusianarts.com/how-to-gene ... -examples/
That is a great link that breaks down DHV stories and basically helps you to create your own.
Also search around forums and the internet for A2 material, There is sooo much you can use for when a conversation dies.
Also Multi Threading is good so that you never run out of things to say.
Hope this helps