Be more Persuasive

Have you ever had a conversation with someone when you start off saying something and after the course of the conversation land up agreeing to the complete opposite?! Well this is one of my biggest weakness. 

Its not that the other person is being malaciously manipulative.Its just that, i give so much leverage, (so much for being polite), that i often hesitate to say something that might upset the other person. Its a big disadvantage. I think i should talk first and talk more.. maybe that will help. But sometimes we just run into "walled" personalities, who don't want to hear anything to the contary of their opinion, that it becomes difficult to convince them of anything. There are others who selectively choose what is convenient for them, and ignore the rest. These two personalities are the hardest to combat. They are invariably pessimsitic  and moan at every hurdle.

Here's something i read about handling these kinda people..and being more persuasive at a conversation..

• First do the work of defining what you really want your audience to know. Otherwise you will simply get lost in your words and either give up or come out the other end not knowing what it is you were trying to say.
  
• eliminate what is of no importance. Why? Because just as you don't want your key ideas to get lost in details, you certainly don't want them to get lost in elements that have no business being there in the first place.
  
• Say what needs to said in minimum number of words.
• People will listen to you better if you show them what they gain by listening to you.
• Display logic and give presise information..it will immediately get the attention of others.