The Lenny Up is a soft structured carrier made from woven wrap material, fully adjustable from birth to toddler. Here is a video from Lenny Lamb showing how to adjust it.
Here is a video which shows how to put baby on in a front carry from Tula. It applies to this carrier also:
https://www.youtube.com/watch?v=PXOjVyjxahc
Here is an alternative way to put it on:
https://www.youtube.com/watch?v=gwIG8iDLmeA&list=PLIqcyORjiqIfjSyLU6iTzUNUg8I6O3vXP
Here is how to put baby in a back carry by using a secure hip scoot:
https://www.youtube.com/watch?v=oD5P9zghwGM
And an alternative way:
https://www.youtube.com/watch?v=2u_b2coQD34
More info about soft structured carriers can be found here: