If I declare an NSString in my header file as follows: 

```
{
  NSString *testString; 
}
@property(nonatomic,retain) NSString *testString;

```

Then synthesize the string in my .m file, what is the correct way to initialise it?
If I don't write:
 `self.testString = [[NSString alloc] init];`

then the it is never initialised, but if I do, then isn't the string being retained twice? Or should I initialise it some other way, such as:

`self.testString = [NSString stringWithFormat:@"%@, sampleText];`