If your considering to order the new Huawei P8, then you should also check if the Sim card you are currently using fits also for the new smartphone. Because the Huawei P8 requires the currently smallest Sim card format, which is available. The smallest size is a nano sim card.
Thus if you want to use the phone function and the mobile data network of your mobile operator with the Huawei P8, you need such a Nano-SIM card. Have you been using a standard or a Micro Sim card for your smartphone there are now three different ways:
1. You have a Sim card with nano-perforation
This is the easiest option. Just press out the Nano sim card from the existing sim card along the perforation.
2. You have a Sim card without nano-perforation
For this purpose, there are so called "Sim card Cutter" available. Sim card cutter cuts out the Nano Sim Card size of your standard or micro Sim card. Such Sim Card Punching already exist for little money on Amazon
3. Order a Nano Sim card from your mobile carrier
You can simply request a new SIM card from your mobile operator. You know now which Sim card the Huawei P8 requires. Have fun with the new smartphone!