Embassy accepts 2 by 2 color photo (they need 3 copies). Don't stick the photo in the form. Send it with the form paper clipping it. They will do the necessary adjustments. Be clean while filling the forms and don't forget to send a return envelope with your recent US address on it. Nepalese Embassy can actually send you the form if you cannot find A4 size paper here in the US. Along with it, they will also send a paper with detailed outline about how to fill out the application and photo requirements. Just follow those guidlines properly, you should be fine. It takes about 3 months to complete the whole process.