Usually, anything less that 1 year could be a red flag. It's depends on how many job you already have and how long they are. It won't look good on your resume, if you are in your 1st or 2nd job and none of them are more than a year. It won't be a problem, if you are an experienced with more than 3 jobs, with at least one 3 year or more.
I would suggest you to start looking while you are still working in this job. If you can find the job you really like and put in a good 2-3 years in it. When you start looking for another job, no one will care if you only worked for a few months in the job you have now.
Regardless of the years you have, it is better to look for a job while you have a job. It give you more bargaining power. You will have the time to pick and choose the job that you really like, without worry running out of $$ and ended up accepting job and offer that is not what you really wanted.