questions about using EAD

i am now an H-1b holder working in the university. my 485 is pending based on my hu*****and's GC application. i am now thinking about changing job to a company. i think i can use my EAD for any job changing. but my question is, can i use my EAD right away, or do i need to do any document work (such as transfer my H-1 to H4, etc.) before i use EAD? thanks a lot!