Start your VS 2010.
Start a new project, then Select your desired language (C# in my case).
Then select SL Application, give some name to the app (say HelloWorld...). Now move your mouse pointer to the glowing button named 'OK' and apply a force of 1 Newton on left mouse button or simply press 'Enter'.
It will ask you if you want to add a hosting webpage for this dummy app.
Do as shown.
Thats it now you have you project ready to be developed.
You can see this thingy in solution explorer.
Your project's main page is Page.xaml and its code is in Page.xaml.cs.
Now in the page Page.xaml, under the main <Grid x:Name="LayoutRoot" ..
type <Butt... and it will show you all available controls... something like this.
Add it to the XAML file and inside Button tag add attribute as shown below.
Now you have a push me Button in your interface. You can check it by compiling and viewing in browser.
Now add an event handler on click event of this button like this.
Typing Click will show you. Add this now this event is present in your Page.xaml.cs.
Open that Page.xaml.cs file and see that event lying there waiting for some code stuff.
Add code in that event
//MyButton is id of the button I added.
Now 'F5' your VS and TaDaaaa... The app is there. Push your button and the content will be changed. Thats all.
One thing more. Did you notice it was not a Hello World!!! app at all. It was kinda Push Me hard!!! app
. Anyways, take care.