Click on the letter then, from the 'Drawing Tools' tab, click on the 'Position' icon and choose whichever kind of centring you want.

Note: You'll need to switch to Print Layout view to see the letter properly centred.

__________________
Cheers,
Paul Edstein
[Fmr MS MVP - Word]

Thanks

Itried all those options but it only moves the shape with the M inside.I could not get the M inside the shape to be in the centre...maybe i missed something