When we say "by oneself", we often refer to an action done alone and without any help or company. However, there are plenty of synonyms that can be used to describe this state. Words such as solitary, singular, independent, self-made, self-sufficient, and lone are some examples. Additionally, phrases like "on one's own", "single-handedly", "solo", and "by your lonesome" can also be used to describe the act of doing something alone. These synonyms are perfect for expressing one's independence or self-reliance in situations where it is necessary to do things alone.