Providing your body with stress-challenges is the place to start, movements that are easy for some people, thereby not providing them with a challenge, may be enough of a test for you and your situation. For example, if you need to put your hand on a chair or table to help balance as you do the movements shown, then do that to start off with. If you can’t swing your leg very much then swing it a little, if you can’t swing it at all then tap it to the floor or run it along the floor.
Gradually as your body responds to the level of stress-challenge you are providing, it will become easier, and you will be able to increase your movement until you have upgraded your mobility.
How long will it take to see some improvement?
Does it matter? Honestly. If you are slowly getting more mobility, better balance, building muscle, becoming more flexible, then by definition you are not getting worse, the only other option on the table!
In a world where everyone wants quick results the story of the “Tortoise and the Hare” in which the small steps and commitment of the Tortoise, wins over the Hare is the mindset to embrace.
To do this “Tortoise” approach, you need to do start doing some form of movement that is simple to do, enjoyable and gives the best possible return for the least effort, and in the minimum amount of time. As you progress you become invested and engaged in challenging and complex movements.