I've H4, but still in India...Can I apply for H1 from india and travel to US on H4 ?

[SunithaAshok]

Hi
I got H4 visa in Dec 2004, but still I'm in India, never travelled to USA.
I'm planning to travel to USA in April mid or in May. I want to apply for H1 in April.
After applying for H1 can I travel on H4?
What is the process to apply for H1 when I'm in USA on H4?
What is the process to apply for H1 when I'm in India and never visted to USA on H4 ?
Please suggest me what to do, Do i have to come to USA before April to apply for H1
or else can i apply for H1 from India and travel to US in May ?
I hope my question is clear.
Please suggest.

Regards,
Sunitha