When requesting clearance there are several important items that you need to include, these are Aircraft type and stand number. The aircraft type is used so that the controller can verify the aircraft type, as this plays an important factor in allowing other controllers to guess your speed and wake turbulence category. The stand number allows the controller to be able to verify that the callsign correlates with the correct radar return and that you are where the controller thinks you are as a tug may have moved the aircraft and a different controller may not have updated the flight strip.
You also should include the ATIS information and the QNH in your request too, however, the controller can give you this information in your clearance.
As there are 4 bits of information that you as a pilot need to give the controller, we always recommend that you plan ahead and have a pen ready as you may be issued with a reroute. You need to pay particular attention to the letter as this denotes what runway you will be departing from, there is also the potential that if the airport is busy, then a slot time may be issued, make a note of the time and if you are unsure about it then ask the controller in a private message about what exactly it means.
TOM4575: Gatwick ground, TOM4575, B738 stand 102 information Q, QNH1013 request clearance to Bourgas
KK GND: TOM4575, Gatwick ground, cleared to Bourgas, MIMFO1X departure, squawk 5264.