Believe it or not my plumhead also has an affinity for human feet! My suggestion is to try covering your feet, more. Maybe buy a new pair of slippers? A new pattern or texture maybe something not familiar to your bird? (I am unsure if you already tried this, so sorry if it seem obvious
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My other tip is to try to procure new types of toys and new foraging toy ideas. If your guy has to work harder to finding food, he will have less time for your feet. You could also try to mix up the routine, try adding spontaneous training sessions into the day, breaking up the usual routine. I would also disengage from your bird if they are expressing mating behaviour toward you. As an example, lets say he is starting to drag his beak, pin his eyes and is generally getting a bit worked up about your feet; you can leave the area. Disengaging with your birds advances can reinforce that you want to stay in the friend zone, and don't consider him a mate. He will likely be persistent, but in my opinion it is better than leading him on. We should do our best to always stay in the friend/flock zone with our birds. Don't forget that flock relationships are based on common preening, foraging and eating. Make sure your bird in involved in the daily flock ritual, like eating or watching you work, most of your interactions with your bird should be at a distance. Touch can be very stimulating, and especially during this time of year can confuse your bird. Another way to disengage from your bird is to turn your head away and to pretend to preen your hair. Preening is used by birds as an appeasement gesture to communicate that they are just relaxed, not a threat, or in this case- not interested in mating.
I am unsure if any or all of these tips will help you, but hopefully they give you some new ideas and things to try. Patients is key. it isn't his fault he loves your charming feet.