When I played The Sims back as a little kid in the early 2000s I didn't know how to play, how to search properly and didn't know how to look for tips and guides. So I would rely only on what people told me and stuff that I'd learned myself while playing.

At one point I remember that I took a brand new notebook/diary with a cute rabbit cover and pink decorated paper, that I had recently got as a gift, and labelled it as my "The Sims Tips" and started jotting down tips and how to play. I would write stuff like "don't have a baby until you have money" and the basic cheats like "move_objects".

After playing The Sims as an adult I realised that it wasn't because of me that my sims kept setting the house on fire, it was the game that was hard (The Sims 2 and 3 are really easier than the first game of the series, each game got easier than its ancestor). So I decided to learn how to play the game again and I have some knowledge to share here.

Classic The Sims cheats, just press Ctrl + Shift + C to open the cheats box and type them. You can select text on the box with the mouse and use Ctrl + C/Ctrl + V to copy and paste text.

List of useful cheats:

• kaplaucius: adds 1000§ to your sim funds (doesn't work on The Sims Complete Collection, as far as I remember it only works on base game).
• rosebud: adds 1000§ (works on The Sims Complete Collection).
• Extra: type !; at the end of the money cheats and at each pair of these punctuation symbols you repeat the last cheat that means that you get more 1000§ per symbol.
• move_objects on/off: permits you to delete/select/move any object on the lot, even sims, pets, the mailbox and the yard trash can. Type on to activate the cheats and off to deactivate it. Also permits to build/place objects on the out of bounds grass area of the lot and the road (tip: don't delete the mailbox, outside trash can, the portal to sims walk in your lot and the carpool but you can delete the bills with no consequence).
• Nessie: shows Nessie in the river on the neighbourhood view, she appears on Old Town, Downtown and Vacation Island.

You can find more cheats on The Sims wiki but I've tested them on my game and they didn't work on my game.

Unsorted list of tips and tricks that I've used on my game, I've created them based on my experience playing the game and mixing the cheats.

• Use move_objects to delete your own sim and it fills all your sim needs, your sim will disappear but just click on their portrait that the sim will appear next to the mailbox (this will reset their skill points to the last time you've saved to save before doing this).
• Great trick to make friends easily:
  • Download one power-nap recliner (it'll be used later);
  • Build a lot on Old Town that can have any appearance you want but it'll need to have a room to satisfy each sim needs: a normal bathroom (I think that you can only add showers/bathtub with the Superstar EP installed), a room with food vendors or restaurant, a room with entertaining objects to raise a sim's fun need and a bedroom (you'll use the power-nap here to make a bedroom).
  • Now have your family visit Old Town and voilà your sims can fill his needs even outside home and you can focus on building relationships with your neighbours (๑•̀ㅂ•́)و (you can repeat this on Magic Town and Downtown too but there the game generates random townies instead of bringing your sim neighbours to the lot so keep that in mind).
• The Sims doesn't have a week, so no weekends either, but you can create your own weekends for your sims if you make them skip a work's day. If a sim misses work and alternates with days going to work they won't risk losing their jobs (even if you receive a phone call saying that you sim will be fired they'll only be fired if they skip 2 consecutive days at their jobs). Alternatively, you can download the call work phone plugin and stay home forever.
• A child sim can be "home schooled", just make the sim study with a bookcase or a computer and they won't need to go to school anymore.
• Always have your sim study culinary before trying to cook something, I realised that a sim with 0 skill points in cooking is more prone to set the house on fire while trying to cook food so I always made them have at least 1 point in cooking skill before using the stove/grill (and it has worked most of the time).