First of all Crucian, you have put your finger on the only downside of using this rig and that is you have to tie a new one every time you need to replace the bait.
I actually tie the rig the other way round. First I take a length of the most supple braid I can find. I tie on the hook using a half blood knot to a straight eye or spade end knot if it is an offset eye. Then I thread on the pop up and push it towards the hook. I then add a shot between hook and pop up so that it is just enough to turn the pop up to make the hook hang below it but not enough to sink the pop up. I would use putty but it is hard to find in local shops here. Sometimes, just the weight of the hook is sufficient. It depends on how buoyant the pop up is. The hook pattern does not matter too much but I suspect an offset point might help. I used to think that the gap of the hook should be half the width of the boilie to avoid snagging the line hanging down the side of the boilie but in practise an even a bigger gape never snags. I have done a lot of sucking and blowing with that “artificial carp mouth” to test this.
The line is then tied to whatever weight you are using. I tend to use 70 grams inline but the type is not critical. The length of line between the boilie and weight needs to be the distance above the bottom you want your pop up to fish.
If I am really honest I rarely use pop ups because most of my fishing is over clean ground and I seem to get more takes on a bottom bait. However, I use a very similar rig which is modified to work on the bottom. I rarely miss a take because it is self-hooking. If you have a 20 mm boilie and the bend of the hook is 20mm below this, the hook describes a huge 40mm arc inside the carp’s mouth. It is virtually impossible for it not to find a hook hold.
As I say in the video, the sudden movement the carp feels inside its mouth causes it to bolt immediately. There are no tentative bites, they are all one toners.
I hope someone finds this useful.
In reply to Snowmanstevo, the whole thing has been filmed using the slow motion feature on my 'phone. The hook whips round quite quickly in real time giving the carp no chance to blow it out.