In the VBE click on Insert.
Click on Module
Click back on Insert
Click on Procedure
Give it a name (No spaces)
Between the name and End Sub type in:
UserForm1.Show (Or if you have changed the name)
Back to the sheet from the Forms toolbar click on the button icon.
Click on the sheet where you want to put it.
Highlight the macro you want to attach it to.
Click off the button.
Right click the button and click on Edit Text
Rename the button