If there is any peeling — and there usually is somewhere — it's essential to scrape off any loose paint. This doesn't just mean the parts that are already separated from the wood and ready to fall off on their own. Each spot where paint has peeled loose needs to be scraped thoroughly until you can no longer get the sharp corner of a putty knife under any of the surrounding edges of paint. Then, the bare spot needs to be sanded until the paint edges are smooth.
There are cases where apartment complexes allow you to choose from a color wheel of neutral hues before you move in. Some charge a fee for calling in a painter to do the walls, while others offer new paint as a benefit of moving in. If you're not a fan of neutral colors, consider looking for an apartment that allows you to paint the walls a more expressive tone. Otherwise you can invest in boldly colored furniture and posters.
The right paint stroke to use in interior painting is highly debatable. It's not a talent as much as a skill that is learned through practice. Many experts paint in a “W” pattern when using foam rollers, but others simply roll up and down then sideways with either brushes or rollers. The motion isn’t as important as making sure that the application is even and drip-free across the entire area. However, technique is important when you're covering over wall repairs.