I'm not a fan of front facing carries for the wearer or the wearee, it's not ergonomic and tends to force babies back to curl the wrong way. I can't really offer any pointers other than to watch how you "load" the baby, his knees shouldn't be up that high.
We used (and even still use) the tummy to tummy hold almost exclusively. If you bring the fabric up behind LO's head with his head sideways it's great for sleeping. https://zolowear.com/WearingSnuggle.aspx
Re: Q about ring sling
I'm not a fan of front facing carries for the wearer or the wearee, it's not ergonomic and tends to force babies back to curl the wrong way. I can't really offer any pointers other than to watch how you "load" the baby, his knees shouldn't be up that high.
We used (and even still use) the tummy to tummy hold almost exclusively. If you bring the fabric up behind LO's head with his head sideways it's great for sleeping. https://zolowear.com/WearingSnuggle.aspx
I love Zolowear's ring sling instructions here: https://zolowear.com/Wearing.aspx
If he's happy then I wouldn't worry about it his feet being up. You don't want him sitting on his feet/legs, though.
How does he like being held otherwise? If he'll sleep upright in you arms, then try tummy-to-tummy.