Hi and welcome
6 months is a great time to start EASY, but perhaps you might find it easier to break it down into little stages to help you stick with it?
So at the moment it looks like the current routine is working ok for you and the main issue is breaking a dependence on feeding to sleep and getting her into the crib - is that correct? Could you perhaps tell us how long she usually naps for each time?
I think it's important to have realistic expectations - if she's only ever slept in your arms whilst nursing, then putting her in the crib will inevitably lead to crying to begin with. She doesn't understand why things have changed, and that's the only way she can communicate that feeling to you. An hour or more of protest really isn't unexpected at all at this stage - missed naps are normal too. Usually sleep training does cause short-term over tiredness but usually that starts to work in your favour at some point
How you approach this really depends on if you're more of a 'gently gently' person or a 'rip the bandage off' type. If you prefer the very gentle approach you might find it helpful to read this:
https://babywhispererforums.com/index.php?topic=52857.0 It often takes quite a bit longer than the alternative approach but possibly might involve less crying. The other way is to use shh pat/PUPD (make sure you read the FAQs) - accepting this is a bigger change at once and is therefore likely to lead to more short-term protest, but probably a quicker result overall.
Whichever you choose, consistency is key. For naps we usually suggest that you should try for 45 mins, then if not settled, take a break for a few mins and try again. At bedtime or in the night you go for as long as it takes. You might want to try just naps to begin with, or just nights, but both together gives more chance to practice
Up to you though which approach you feel suits you and your LO best.
The rolling around/sitting - you should just ignore this really. Lots of LOs are all over the place before they settle to sleep and it's not your job to stop her. What you are aiming towards is that she can roll about all she wants but eventually get herself comfortable and go off to sleep without your help. Just a small caveat to that - if it happens for a long period in a LO who knows how to sleep independently, it would make me think they were undertired (too short A time) when they were put down. It's not possible to say that yet with your LO but if it's a consistent issue I would probably aim for a bit longer A time. As a minimum I'd probably aim for 2.5h if you can just to make sure you don't risk her fighting because she isn't tired enough.
I hope that's some help to begin with - please come back to us if you have more questions