hi fellas,
i know its been said many , many (!) times before that there are lots of ways to do it, i would suggest to anyone new to it, to try not to get intom habit of marking out with sellotape, masking tape etc for siliconoing as its not neccesarry once you've done it a few times with soapy water, a fairy liquid finger(ooof!)

and a calm mind, (eg not despreatly trying to get the f**** sealing done casue you alreay running late!)
just think think that you will be causing yourself extra time in the long run if you always stick with that,give it a go freestyle! worst happens is you cover it wait really soapy water pull it all off and go again... just a though...