I find it to be a more intense and immersive experience. The mental highs and lows tend to be higher and lower than when you have company. For me, personally, it's such a strong experience I "need" less of it than group hiking. My longest unsupported group hike has been 9 days, my longest solo one 5 days.
Invest some time planning on safety. Local knowledge (weather extremes, wildlife) is crucial.
I've heard someone say as a general rule: "don't run". Both literally and figuratively. Another one is: when in doubt about whether or not you're lost, stop immediately, have a break and a snack and analyze the situation.
Starting with overnighters, then weekend trips, you start to figure out what you need to pay attention to: do you tend to get blisters, do you have challenges remembering to keep hydrated, are some foods problematic etc.
Have fun out there!