Ok. So you’ve got yourself to your instrument and you’re about the play . But what do you start with?
If you’re learning a song I always say to start with playing your song(s) through and just identifying the parts you’re not the strongest at . Then go straight into the parts you struggle with and work hard at correcting what you do wrong . Don’t hesitate as you have the most energy and patience at the beginning of a practice session. After that you can play through the song and should be rewarded with how much better it sounds ! Treat yourself after the session by playing something that’s easy for you or you’ve previously learnt so you feel like you’re really playing your instrument !
If you’re prepping for exams I always say to start with your least favourite (and therefore usually weakest ) area . For me it was always sight reading! Start there and focus on it the most. Do exercise after exercise and even though it may take months , you WILL notice a difference ! Then I go to the next most difficult section (for me Scales and arpeggios) and then treat myself with the section I’m most comfortable with . A system like this always helps with using your most effort on the parts you need it for and hopefully keep you inspired and happy after each session as you can hear yourself playing well and with little effort !