One piece of advice that new teachers often get is to observe master teachers and learn from them. This is good advice! You've been in your classroom for a few months now, and you have a routine down. Now might be the time to work with your principal to secure a substitute and spend some time in your colleagues' classrooms. Maybe you'd like to observe a teacher at your grade level or in your department. Or maybe you've heard such great things about the innovative teaching of someone way on the other side of the building. Many principals are very amenable to facilitating a day for new teachers to observe the most effective teachers in the building. But even if you can't schedule an entire day away from your classroom, perhaps you can work ahead to use your prep time a few days to observe.
Observing another teacher's class can provide you a chance to see how other teachers run their classroom, and provide an opportunity for you to reflect on your own. More than just meeting and talking with your grade level or department colleagues, you get to see them in action. It can be wonderful professional development for you. I know I learn something every time I'm in a teacher's classroom. It can be most helpful if you go in with some sort of frame for the observation - are you looking for classroom management ideas? How the teacher works with small groups? Maybe transitions are a tricky time for you and you want to observe how other teachers deal with transitions. Are you looking for ideas to work with EL students? Wait time? Questioning and/or discussion techniques? There are lots of things you can consider in prep for an observation. And though not necessary, a framing question for your observation may help you come away with more specific take-aways.
And yes, you did lots of observing during your practica and student teaching. However, this is an opportunity to observe teaching knowing the exact context of your classroom. This will make observations more focused and helpful, because you can have in mind all of your students and your content and your instructional practices as you observe. Plus, it can help you understand your school community better - when you see more teachers in action, you better understand the culture of the school,