If you talking about computer storage then you can manage this problem simply by following ways:
1. You can update your old lower capacity Hard Disk Drive with higher capacity drive (usually with 1TB to 4TB, which is easily available at reasonable price tag)
2. You can write your old data from your existing disk to DVD or on Blu-ray disk to reduced burden on your hard disk drive.
3. You also can manage disk space by simply deleting old and unnecessary data from your disk.
Hope the above ideas will help you.