Free Food
When you reach Player Level 5 you will be able to unlock your first hobby. If you select the cooking hobby you can cook large plate meals for free, feeding your Sims multiple times without the cost of snacks.
Restore Energy
Keep an eye on your energy levels and restore them accordingly. Energy is restored by sleeping, Hygiene by using the toilet or shower, Hunger by eating and Fun by watching TV or dancing to the radio.
Daily & Life Goals
Try to complete your goals whenever possible, they are simple to achieve and they will earn you a lot of EX, Simoleons, and random rewards.
Household
Remember that having high friendships makes completing goals a lot easier, especially if you do it with Sims in your house.
Save Your SimCash
Don't waste your SimCash on skipping time, it is more beneficial to save it for items later in the game such as beds that allow for near instant recovery and baths that instantly fill Hygiene.
Change Careers
Don't be afraid to switch careers if you fancy a change. Although the different careers work in a similar fashion and offer similar rewards you will find that the environment, exact actions and benefits will differ slightly. If you do decide to change career there will be no penalty and you will retain your level in that career and can switch back at any time.