To apply for the PET (Pre-Engineering Test) examination after Class 10th, you'll need to check the eligibility criteria and application process for the specific exam and institution you're interested in.

Here are some general steps:

1. Check Eligibility: Ensure you meet the age, qualification, and other criteria specified by the exam conducting authority.

2. Choose the Exam: Decide which PET exam you want to apply for, such as JEE Main, JEE Advanced, or state-level exams like MHT-CET or KCET.

3. Registration: Fill out the online application form on the official website of the exam conducting authority.

4. Upload Documents: Submit required documents, such as your Class 10th mark sheet, identity proof, and category certificate (if applicable).

5. Pay Application Fee: Pay the specified application fee online or offline, as per the instructions provided.

6. Submit Application: Review and submit your application form before the specified deadline.

Some popular PET exams and their application timelines are:

- JEE Main: Typically held in January and April, with application forms available from September to January.

- JEE Advanced: Held in May, with application forms available from May to June.

- MHT-CET: Held in April-May, with application forms available from January to March.

- KCET: Held in April-May, with application forms available from January to March.

Please note that the application timelines and process may vary depending on the exam and institution. Be sure to check the official websites for the latest information.