The way I like to transition to outdoors with my redtails is this:

When I think they are ready, I do a normal training session indoors, but when I pick them up the last time I hood them and take them to the mews/weathering area where they are free lofted. The next day I go in, wait for the bird to calm down and follow the same basic approach as when they were indoors, approach, tidbit, back away until they are comfortable with that, then step to the glove, then hop. they are free in the mews until they are flying the length of teh mews with good response. The trick here is it is tough to weigh them as I don't restrain them at all until I am ready to take them outside, you need to pay really close attention to what they are eating and how they are responding. My favorite thing about this routine is if I screw up and the bird is too high to behave, I turn around and walk away and try again after a little while. There is no need to collect the bird as she in already 'away' as it were. Provided previous steps of manning and training indoors were done well this works very well for me.