There are two ways to it:
One: Apply for job portals. Wait for openings. Wait for callbacks. Basically wait for your luck to someday open up.
Two: Create your job. Figure out what you want to work on. Start working on that, before you have a job. Then apply for internships. Write cold emails, stating how you can help them. Create your own luck!
There are always two ways to do something. The second one is always harder, but makes your life easier!