Bought Jasco Generator. Give tips to use please

First time ever in life, i have bought a small generator. I do have UPS but sometimes electricity fault is big and i needed backup. Its a petrol generator. Jasco around 500w. So two fans with one saver is enough.

What i want advice from you is, can you tell me, how to take care of it. What to do and what not to do. Any tips to reduce the sound. I don't have problem sleeping because it is kept in balcony but i still feel, if i can reduce the sound so neighbors don't get disturb.

Also advice regarding, petrol/oil mixing as it is two stroke. Help as much as you can to make me understand.