You can prepare H1-b applicatiton on your own but your employer (HR person or your manager) has to sign on the forms. The return address should also be your employer's address. You do not need to hire attorney for your filing. Just check I-129 instruction properly and you would know what forms and supporting documents are required. It is very easy steps if you follow properly. There are lots of instructions on online that you can search and find all required info.

You do not need a lawyer to file any immigration matter..........