Im not sure what you mean 'so that the text wont dissappear behind the frame if I minimize size button'.
For all the caption text to fit in the CommandButton you have to resize the button. How much you have to do that depends upon the font type used (Arial etc) and what font size you use. For example, Arial Narrow is a thinner text type than Arial and you can also change the size down from the default of 10 to say 8 or 6 etc.
There is also the ability to wrap the text so its not too wide (WordWrap = True) plus the button can be autosized to the minimum size needed that will fit all the caption text (Autosize = True).
You also have the ability to insert a picture into a button so you could create a picture and overlay text within the picture then add the picture to the button. You would also need to remove the text in the caption as this will still appear in the button.
Thats about exhausted all the sizing options im aware of.