How , where &/or when to use He sido or he estado?what is the grammatical difference?
When does one say he sido or he estado
2 Answers
What sort of detail do you want here?
I'll guess that you understand the Present Perfect, it's only the 'Ser/Estar' difference you're querying?
A couple of examples to demonstrate:
He sido una tonta. (I have been a fool) Describing yourself, a characteristic you had at that time.
He estado tan triste sin ti. (I have been so sad without you.) Describing how you felt. You could equally substitute this one with:
Me he sentido tan triste sin ti. (I have felt so sad without you.)
but you couldn't substitute 'felt' for 'been' using 'Ser', if you see what I mean, because if you did it would mean that you felt foolish but not that you considered yourself a fool.
I hope others will add to this because I'm not sure I explained it well, but the examples I gave are accurate.
This may help 
Ha sido y ha estado
