What do you advice for a horse who, in lunge, tends to want to drift in towards me? I try to make sure I’m staying towards his shoulder.

I agree with Natahlia. If you have a lunge whip keep it out so you have a sort of space bubble. If they start to drift in you can take the whip and just poke their shoulder/belly with it to remind them to stay out. Good luck!
Also say out when he or she does that
Hi Emilia

My horse does the same thing, if you have a lung whip you hold it towards him or her so it warns him or her off. Hold the whip so it is pointing towards its tummy :) hope it works
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