For me, the mental effects were almost instant. Like, within a few days. I think that was mainly because my body was being shown the new hormones & it was adapting. I didn't get much visible changes within the first few months & even after a few months, the changes were subtle. The changes will always be subtle. They may happen quickly, but still subtly. You may not really even notice them that much. The most memorable thing I remember was the day I realized my thigh gap was gone. That was about around 6 months in. My boobs didn't start budding til 2 months but that's normal. Some peoples start growing a lot sooner though.