Body image : how can I improve my body image self confidence ?

Hello – I have body image issues:  When I look in the mirror I think “I must work on that”, “It’s not enough”.  Sometimes I know people can be attracted to my body but often I think on the contrary.  I’m not beautiful enough.  Can you help me ? What can I do before going into  ladder thoughts?  Also I’m unsure how to do a ladder thought, they all sound fake!