There's quite a lot you need and some things are more complicated than others to make. Hair is especially difficult, but once you've practiced and got the hang of it, it should get easier.
If you've never created custom content before, I'd definitely recommend starting off with something relatively simple like custom pictures, patterns or make up - just so you get a feel for how things are done before moving on to more complicated things like clothes and hair.
You're basically going to need a graphics editing program like Photoshop or Gimp, along with a 3D meshing program like Milkshape 3D or Blender - there are also a few programs you'll need to access the files from the game such as TSR Workshop, CTU, and S3PE ... but when you check the guides for your instructions, they'll show you exactly what you need.
The best guides are on Mod The Sims, they have a directory of tutorials you can use, so just go here: http://www.modthesims.info/wiki.php?title=Sims_3:M... and choose what you'd like to make - all the guides have links to all the things you'll need before you even start, so hopefully you can find everything pretty easily.
Comments
There's quite a lot you need and some things are more complicated than others to make. Hair is especially difficult, but once you've practiced and got the hang of it, it should get easier.
If you've never created custom content before, I'd definitely recommend starting off with something relatively simple like custom pictures, patterns or make up - just so you get a feel for how things are done before moving on to more complicated things like clothes and hair.
You're basically going to need a graphics editing program like Photoshop or Gimp, along with a 3D meshing program like Milkshape 3D or Blender - there are also a few programs you'll need to access the files from the game such as TSR Workshop, CTU, and S3PE ... but when you check the guides for your instructions, they'll show you exactly what you need.
The best guides are on Mod The Sims, they have a directory of tutorials you can use, so just go here: http://www.modthesims.info/wiki.php?title=Sims_3:M... and choose what you'd like to make - all the guides have links to all the things you'll need before you even start, so hopefully you can find everything pretty easily.
Have fun!