One of the things Rafael gets asked the most is what you should and should not when you practice. His first 'lethal weapon' is ... the metronome!
This is one of the best tips Rafael has for flamenco guitar students – to make sure you own a metronome. Some players (such as Rafael) likes the nice mechanical click of physical metronomes – and you can see the physical distance between the notes – which is never a bad thing when it comes to practicing with a dancer.
Online flamenco metronomes such as Acompas come with default settings that adapt to the palo (e.g. buleria, alegria, rumba) which is handy if you are happy to use a website or app – handy if you're on the move.
Rafael also recommends having a mirror (or computer camera) so you can keep an eye on your posture and playing - bad habits will inevitably creep in for all players, but at least with a mirror you can catch yourself slipping.