You can increase the size of AWS EC2 instances using the below steps:
1. Inside your AWS Management Console, go to the EC2 page.
2. Edit the instance you want to change (from micro to large, for example)
3. Keep the instance in a 'Stopped' state and click the 'Instance Actions' menu to choose 'Change instance type'.
4. Choose the instance level you want to run like (small, medium, large). Click 'Yes, change''.
5. Restart the instance in question.
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