I've played lots of Harvest Moons (yes, plural) on Super Nintendo, Gameboy Color,
and the N64.  I've got some advice; 

1)Don't waste time.  Always be doing something, always have a purpose.  It doesn't pay
to sit around and do nothing. 

2)Time stops in buildings.  This is THE MOST IMPORTANT quirk of the game.  If you use
this tool wisely, your efficiency will multiply beyond your wildest dreams.  Combined
with number 1, here are a few specifics: 
    When harvesting crops, put them in your backpack.  This way, you can carry nine
(eight in the backpack and holding one) veggies at a time, and save lengthy trips to
the BOX. 
    When you're able to harvest, do it in between other jobs.  Fill your knapsack 
upon leaving your house in the morning.  Go to the cows.  Empty the sack in the cow bin
(time is stopped, remember?), and milk, feed etc.  Go out and fill your sack again, then
care for chickens.  Empty sack in chicken bin, care for chickens.  Switch to watering
can, fill it after the chickens, harvest, etc. 
    GET THE GREENHOUSE.  The thing is 16x16 plowable squares, with a bin and a water
source. Time is stopped.  Unlimited money, need I say more? 

3)Plan your crops.  Use a 'fat c' method with regenerating crops: 
                x x x 
                x x 
                x x x 
and use a 3x3 grid for your spring crops after you have the gold can: 
                x x x 
                x x x 
                x x x 
Leave yourself plenty of room to approach your crop area to water it. 

4)Plant turnips first, harvest them for $$$$, then switch to potatoes.  'Taters are
the best crop for net profit.  Cabbage grows too slowly, and turnips are too cheap. 
Potatoes rock. 

Efficiency, efficiency, efficiency. 


                                          ---Mr. Ed