My midwife taught me to feel for the head. If you get your hands on either side of the lump you want to identify and wobble it, if it moves quite freely it's the head. If it seems to move the whole baby, it's a bum! It was so easy once she showed me. Feels like you're moving a tennis ball between your hands. So my poor dd had her head wobbled every day to see where she was at lol.