Well begun is half done

If you start off right and prepare properly most jobs will continue well. For example when building a shed it is important to lay the foundations accurately so that the sides and roof will fit properly. Skimping on the planning and tools will tend to cause problems to grow and worsen. "Be prepared" is a good motto. Another proverb "Make haste slowly" contains the essence of many a rueful conclusion as a botched job is contemplated.