Always cut the line to a point and straighten it out first before trying to thread it down the tube. Curly line with a flattened end is almost impossible to thread! Our tube comes in large packets so the coils are kept as big as possible. It is also very supple so it straightens straight out of the packet.
In winter, it may be necessary to warm it through your fingers to straighten it out before threading. If you take tubing off and you’re intent to reuse it then slide it up and down a tight line to get the silt etc out of the middle. It is dry gunk up inside the tube, which makes it so hard to thread a second time.
You can leave line inside it and use it to pull a new bit through next time by simply tying an overhand knot around the new line and carefully pulling through. If you are pushing the tube into the top of a rubber, then cut it to a point before threading. The pointed tube pushes much easier into the rubber.
Never glue the join as it makes it brittle, which will then snap after repeated use. When your tube has finally come to the end of its life cut it up into inch lengths put it in your tackle box and use it for hair stops.