To begin with, let's do the dressing: brown the sesame seeds in a dry pan, squeeze the juice out of the orange. Try the juice to taste – if it is too sweet, add a spoonful of lemon juice. Citrus juice, mustard, sesame and olive oil mix well, it is most convenient to do this in a jar, and just before applying the dressing, shake it well, as the sesame floats to the surface.
Remove the skin and seeds from the avocado, pour over the lemon juice, season with salt and pepper and puree it. Thinly slice the tomato and red onion.
It remains only to arrange the salad, I think, do not need to explain, the photo is clear my version, but here it is best to use your imagination. Salad generously pour the dressing, and to the table.