still can't prune flowers - what am i doing wrong?

which flowers? timing matters more than the cut itself with most of them. the common mistake is cutting spring flowering shrubs like lilac or forsythia in autumn or winter, which takes off next year's buds. those get done straight after they finish flowering. things that flower on new growth can usually be cut back in late winter. for the cut itself, clean sharp secateurs, just above an outward facing bud, slight angle.