|My recommendation is to lay out your Pikkolo carrier, mei tei, or Asian baby carrier face up on a table,
take off the connected buckles from the waistband,
then set them on the table on either side of the carrier *exactly* as they were when you took them off.
Then you flip the buckles vertically, from bottom to top, so that the reverse face is now showing (but the edge sides are still the same, a vertical flip), slip on your Babywearing Belt and put the buckles back onto the black nylon webbing straps. That way you won't accidentally put the buckles back on the wrong way. It's common to take off the buckles and throw them ontothe table, then forget which way they should go back on! Keep track as you do it, and it will be a smooth process for you.
IF YOU TOOK OFF THE BUCKLES, ATTACHED THE BABYWEARING BELT AND NOW YOUR WAIST BUCKLE WON'T TIGHTEN PROPERLY:
No worries, you just have the buckles on the wrong way around. If you look, you will see that there is a bar inside the slot on each buckle. This bar is angled a certain way, and the angle serves to "lock" the webbing in place so that it doesn't slip when tightened. So when you put your belt on, you probably just put one or both of the buckles back on reversed.
If you pull the webbing out of your buckles and look at them, you will see the slim bars around which the webbing is threaded. They have some notches in them. Connect the two halves of the buckles and look at the bars.
On one side of the buckles, the bars will be located close to the outside surface. On the other side the same bars will appear recessed. You want to put the buckles on so that when you are wearing the carrier the bars are closest to the OUTSIDE SURFACE and almost flush with it. Does that make sense?
I'll bet that you have them on so that the bars are recessed. That changes the angle of the webbing so that it will slip through the bars really easily instead of locking tight.