It all depends on you. If you got the job which you really wanted, try not yo refuse it. If you didn't get something that you wanted, just go with the post time first. It would let you gain more experience too.
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You can do either one. If you found a job which is related to your education and you like it, then take this job, otherwise you can work part time.
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For me , trust yourself to work or searching experience first
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