"First hand" is a common phrase that refers to direct experience or firsthand knowledge. However, there are several synonyms that can be used to convey the same meaning. For instance, "directly" is a good substitute when someone wants to emphasize that they experienced something personally. "Hands-on" is another phrase that can be used when someone has had direct involvement in a situation or project. The words "immediate" and "personal" can also be used to convey the idea of having firsthand experience. Furthermore, the phrase "on the ground" can be used to emphasize that someone was present and actively involved in a situation or event. Whatever the context, these synonyms can help add depth and clarity to any conversation where one wants to convey direct knowledge or involvement.