Plant Corn or Carrots. They give you lots of coins.
Get your sims inspired. Then you get more xp and coins.
Plant things overnight. Plant onions or beans.
Praise your dog when it digs up stuff.
Sell Trees. They come with your house and are worth a lot of money.
Save up your LP and coins when you dont need them. You will need them for quests trust me!!!
If you are going to make a sim marry and you have a double bed for them both then sell their furniture and their entire house.
Always keep one sim that you are able to make not made. When you make babies or get the quest you will thank me.
Plant, not cook!
Make sims watch news.
Quests come before ANYTHING ELSE.
Level Up!
Compare. From what I saw, doing 2 minute music 2 times making it 4 minute music instead of shuffle for 7 minutes saves time and xp. 4 minute: 32 XP 7 minute: ONLY 29 XP!!! I also looked at gardens and stove and gardening saves time and money instead of doing things on the stove.
Always keep your sims needs met!
Get hobbies and level up! Chances are they will get you money and XP! They are also sometimes fun to do (making all your sims have hobbies of their own!)