There are a few things to think about when you're skiing.
You can't just act freely and think about yourself. You have to think about yours and oters safety.

• Only those wearing skis (boards) should enter the slopes.

 Choose the slopes that fit your level, and maintain order when riding the lift. 

(If you are new to skiing, take lessons so you are comfortable with the basics and can control your speed, avoid obstructions (including other skiers), and stop when required. Lessons will also help you get on and off lifts safely.

If you are an experienced skier, be respectful of others who are less experienced than you, especially on beginner or intermediate runs. When passing, allow a wide berth and don’t turn sharply in front of other skiers when you pass them.)

When skiing [boarding] down, you should always look forward and sideways for your and others safety, keep a certain distance with other skiers, and if collision is expected, you should either shout to warn others or fall down to avoid collision.

(If you fall and are in decent shape (i.e. not injured), make sure you IMMEDIATELY look up the hill to make sure no one is heading for you, then rotate your body and skis underneath you and prepare to get up. When you are skiing down, you are responsible for the people below you so keep an eye on them as you pass to do it safely.

If you're not skiing alone, always look out for each other.
If you are skiing with someone who becomes injured, stay with them until help arrives. Place skis in an upright “X” to alert the ski patrol that help is needed. Never leave an injured skier alone on the mountain while you go for help. Remember the “buddy system” and stay together.

 The center of the slopes is a space for skiing or boarding down, so you should not walk up or give skiing [boarding] lessons.

• You must not stop at the center of slopes where either the width is narrow or different slopes are joining with each other.

• When you're waiting in line, think about your manners. Waiting isn't fun for anyone.

• When taking a rest within the slopes, you must stay at the edge.

 Bring every trash/garbage with you. Let's keep the slopes clean!