floor leveling

[pat]

hi im tiling with 1 year now.i just seem to have a problem with leveling floors and the right way to use leveling compound over a big area. the next floor i have is a kitchen and utility 50 sq meters. i could see that the utility floor is higher than the kitchen floor,but when i put level from utility to kitchen floor there were low points of 30 mm and then reaching the other end of kitchen it was getting high again.there was still some bumps in the middle.the tiles were 300 x 600 porcelain tiles brick effect. is this normal or what is the best way to deal with this. and what is the best way leveling a floor

[Dan]

I've opened this thread again in a bid to get a reply.