How to stop for loop until the userform complete the first task?

[Deepakgopikannan]

In my process, I Use some conditions. For every paragraphs I want to change based on the conditions. Conditions are applied using Userform in vba using (Click OK event). Here i gave the code

Dim Referencecount as integer 
Dim i as integer
Dim Authorreference() as string
Selection.MoveRight unit:=wdCharacter, count:=1
For i = 1 To referencecount
Selection.MoveDown unit:=wdParagraph, count:=1, Extend:=wdExtend
Selection.Range.HighlightColorIndex = wdTurquoise
Authorreference(i) = Selection.Range.text
UserForm1.Show
Next i

Please Guide me How to stop the For loop until the userform complete the first task. Many thanks in advance