You can use a hot spoon to measure out the Golden Syrup; it is so viscous it can be difficult to weigh or measure otherwise.
You can put the dough into the freezer or fridge if it gets too soft during rolling. Rolling it while soft will be very messy. Adding a little sprinkling of flour onto your rolling pin with help with the rolling.
Leave some space between each biscuit on tray as they will expand as they heat up during baking.
It may not need saying, but the biscuits will have to cool completely before making the sandwiches. Leave the biscuits to cool on the baking tray a little longer than you would other biscuits because they are soft when they are still warm. Once cooled place them onto a wire rack to cool completely.
You can shape the ice cream around the edge of your biscuit for the neatest result, going around the biscuit with a warm knife can help with this.
You can place the ice cream sandwiches on a baking tray and pop them back in the freezer to harden up before serving. This is advisable if it has taken a while to make them and the ice cream has got very soft.
If the sandwiches are for an outdoor party or to be served later, you can wrap each one in a square of baking parchment for ease of transporting. This can also be helpful because once wrapped in parchment the sandwiches can be placed into the freezer for storage. They will last a few weeks in the freezer. If you are popping them into a zip-loc bag, squeeze out as much of the air as possible to prevent freezer burn or a build-up of excess ice.
The biscuits will keep for a week in an airtight container before you make the sandwiches.