basically unless u have specific time constraints or previous injuries or something i would say to work out more often in general especially as a beginner
also i believe uve mis-written ur routine
by convention 3x10 means 3 sets of 10 reps
10x3 is what Waterbury talks about which is 10 sets of 3 reps
also im not sure which Waterbury routine ur referencing that only has u lift twice a week.
u are obviously a beginner and as such should at this point just use a pre-deisgned routine on here before u start to design ur own.
must reads are TC’s Two part series for beginners and his two part series for “designing a damn good program” those should give u pretty helpful guidelines in designing ur own programs but for now i would just check out some pre-fab ones… TC and Waterbury have routines that are effective and easy to understand and u should be able to find spread sheets on here as well