Redmine

Hi

I creat the Redmine enviroment in Windows Server2012 R2.
In the "New issue",there're a lot of "custom fields" which I have created in "setting".
But now I want to change the position of the default fields and the custom fields for the feeling.

For example：(I put the picture in Files)
now：pictureJPG (default model)
hope：changed.JPG (hope model )

How should I do for my Redmine?Should I change source code?