I would like to add that you could perhaps try tossing the ball a little further back than you usually do. This exaggerates the brushing up effect. Actually this creates the brushing up on the ball because if you are tossing it in "front" of you, you are going to have to force yourself to go over the ball. Nice job pointing out some of the basic technical requirments Pawan!
Also, I don't know what grip you are using but continental grip is what's "supposed" to be used (aka hammer grip I think). However, it doesn't hurt to twist the racqeut a little more so you have more of a eastern backhand grip (if such a thing exists - that type you hit a one handed backhand with minimal topspin with). This will also naturally brush up more.
Last but not least, a knee bend forward slash back bend backward will help you 1) watch the ball so you keep your head up through the hit 2) give you some lift so you can go UP onto the ball 3) give you some more racquet head speed.
here's a good link: http://tennis.com/yourgame/instructionarticles/serve/serve.aspx?id=529
Moving the toss further back is a must.
I hadn't really thought much about the knee bend/back arch, but that is a requirment for hitting the ball once you've tossed it behind you.
That's one of the reasons I love this forum. It offers so many viewpoints of tennis. I'm constantly learning new ways to look at all aspects of the game.
Couldn't have said it better.
Sometimes I surprise myself when I can actually go technical on some aspect and I realize that everything I have learn, I have learnt it here and if it weren't for this place I would really have given no thought to anything.
The proper knee bend gives you that classic ATP symbol slash Sampras-like hip forward position which lets you put your whip your whole upper body into your serve. Or so I believe
Here's a picture of what I am talking about right from our tennis4you lesson lounge