Hi Lak,
when you prepare to line the tin with greaseproof ...
measure the depth and width of the side of the tin, allow an extra inch both ways. Cut a band of paper to this measurement. Fold the bottom inch up ( depth ) and snip the inch turn up every inch so it looks like a frill ( this will make it easier to curve round the inside of the tin when lining. Make sure you grease the tin and the band before lining! Grease the frill downwards to avoid tearing it. Sit the base of the tin on the greaseproof and draw a line around, cut the circle out, you don't need any extra measurements on the circle. Grease the circle. Put the band in first then the circle of paper. Sprinkle a little flour on the inside and knock out the excess. That's it! You can use the edge of a pallette knife at an angle to form soft peaks in icing xxx