After you have lowered it and removed all the poles and pegs make sure the doors are open, this will let the air out and make it easier when re-erecting next time. Have to hand the tie cords to tie the tent up when you have rolled it as explained later on.
Pull the four corners out so that the SIG is tight. Fold in half lengthways so that the ring pins are all on one side. Make sure the pins all point out otherwise they may puncture the SIG/tent.
Fold in half again along its length so that the width is now the same as the width of the bag. Normally I now lie on one end and "rolly-polly" along the tent to squeeze out the air. Now fold the rear into the middle of the tent then the front to the middle. Then, fold in half again where these two ends meet.
Squeeze out any air left in again and roll up along the length making sure the pins are still on the outside. As you roll it up tuck in any loose material to keep a tight bundle. Lift one end and slide the tie cord under (I told you earlier to have these to hand!) then tie up, repeat with the other tie.
Bend at the knees (health and safety!) and pick up the tent. When putting into the bag lay one end of the tent in first tight to the end on the bag and then the weight of the tent should make the rest just fit snuggly. Make sure the pins are at the top again to prevent puncturing. Lay in the peg bag and the door mat and it should zip up relatively easily. Make sure any loose material is tucked in so as not to snag it on the zip