@BS9790 I have used a lot of different slings - the best thing would honestly be to contact a sling library after baby is born and discuss options with them.
Some babies like wraps, others won't tolerate them at all but like being in a buckled carrier as they're more structured. They'd recommend different slings for pootling around the house with a velcro baby as opposed to opting for a sling over a pram.
Also, different styles of carrier suit different body shapes - you don't want one that's going to give you backache!
I think when most people think of a sling/carrier they are thinking of something like the Close Caboo which is quite structured but does involve some tying.
Another, more hard-wearing and more expensive option are the Ergobaby carriers, which are classed as 'full buckles', as they don't involve tying anything. They are suitable from birth with an insert and the 360 ones are designed to properly support baby in a forward facing position for when they get older and more nosy. I had one of the original ones 5 years ago, and they are proper workhorses, but there were a lot of dodgy fakes at the time (I don't know about now) so you'd need to be careful where you bought from.
I have also used a half buckle, a ring sling and a traditional woven wrap, as well as hybrids.
There's a site called wearmybaby which has lots of info.