Symmetry is a complexity-reducing concept (co-routines include subroutines); seek it everywhere.
It is easier to write an incorrect program than understand a correct one.
A programming language is low level when its programs require attention to the irrelevant.
It is better to have 100 functions operate on one data structure than 10 functions on 10 data structures.
Get into a rut early: Do the same process the same way. Accumulate idioms. Standardize. The only difference(!) between Shakespeare and you was the size of his idiom list – not the size of his vocabulary.