Depends upon what field you want to pursue.. There are many fields to CS.
You must be already knowing them like Networking, Robotics, Artificial Intelligence, Web Development etc.
The truth about CS in many Colleges is that they only teach just the basics or the fundamentals of the important subjects like Web Dev, Networking, Data Structures. The advanced topics can only be learned either by further self study or certifications.
Now if you ask me about networking there are cerifications like CCNA, CCNP. For web development there are W3C Front End Web Development Certifications and various certificates for subjects like Java, Python, Android etc.
You go for anyone of your choice depending on your field of interest.