How do you say i am awesome in japanese?

There are several similar Words, two of the most common being Sugoi (which I tend to translate as 'Super') and Subarashii (which is usually translated as 'Wonderful'). Saikō (extend the sound of the o), which does sound a lot like 'psycho,' could be translated, 'the best.' The Japanese have also borrowed a great deal of English Words, so it would not be uncommon to hear 'Ameejingu' (Amazing).

You can just say the adjective itself or put together a complete sentence like:

1. Sore WA sugoi yo! (That's super cool!)

2. Sore WA subarashii desu! (That's wonderful!)

3. Anata WA saikō no tomodachi desu! (You are the best friend ever!)