Before you send something breakable out in the UK mail system, you should take the time to wrap it up. This can make it possible for the item to get to its destination in one piece. What you have to realize is that the people who are working with your mail have to work with hundreds and thousands of packages every day. They need to be fast and efficient if things are going to get there on time. This means that they cannot always take the time to be careful, so you will need to do this instead. If you do, you can limit the amount of mishaps and problems that occur.
Some people think that simply putting the item in a cardboard box will be enough. They assume that the hard sides of the box will protect it. This is not always the case. The box certainly can help. About that, there can be no question. However, if the item has not been wrapped inside of the box, it can still slide around. If it slides or bounces violently, it could be destroyed inside of the box even if the box itself does not sustain much damage.
The simplest way to pack things for the UK mail system is just to put old newspapers in the box along with the item. You can use one newspaper to wrap the item, and then you can set it in the box. Packing the other papers in around it will keep it from moving, so it will not be damaged. These papers will also keep any impacts to the sides of the box from striking the item that is inside. This cushioning can keep most things from breaking in the mail. It is important to note that you may want to put some newspapers beneath the item so that it is not damaged from below.
It you want to take things a step further, you can use bubble wrap. This is made from thin plastic that has been inflated with air. The bubbles that are created are not unbreakable, but they are durable enough for most situations. The fact that there are many bubbles means that the wrap will still help even if a few are broken. This is better than newspaper because paper tends to compact while the item is in the mail. The air is pushed out of it, and there is not as much cushioning. Since the air cannot easily come out of the bubble wrap, it tends to hold its shape no matter how long the package is traveling to its final destination.
As can be seen, you need to take some time to make sure that your packages get there in the same shape that they left. The mail carriers will not take any responsibility for things that are damaged or destroyed. This is totally up to you. If you use the methods describe above, the items that you send through the UK mail will arrive safely.