I find it easier to tear the sheets into 4 pieces. That first sheet will surprise you with how it sticks to your fingers etc. Use it to learn. When all pieces are applied, use the brush to wipe away the little pieces of leaf that stick up and finish up by rubbing the leaf down with a soft cloth. Save all these little pieces for future projects as they can be layed onto smaller projects or used to fill small areas.
Gold leaf is too expensive to throw away.
Squeeze out a small dime sized amount of the burnt sienna paint onto a piece of tin foil. Rub your soft rag into it in a circular motion then rub the rag onto the gold leafed piece covering the leaf. When finished use a clean part of the rag to gently polish the oil paint to get the finish that looks best to you. The paint will be deeper in color in the recesses of the object and the gold leaf brigher in the non-recessed parts. It will take the oil paint about a week to dry so you have ample opportunity to live with it and make any changes.