To register your business as an employer with the Social Security System (SSS) in the Philippines, you need to complete the Employer Registration Form (ER1) available on the SSS website. You will also need to submit certain documents, such as your business registration and tax identification number. Once you've completed the form and gathered the necessary documents, submit them to the nearest SSS branch. For more detailed guidance and to ensure compliance with all requirements, it's best to check the official SSS website or consult with a licensed professional.