Skiing / ski jump

Slide usual paper over abrasive paper at various speeds to achieve a nice variation of ski sounds.
– Ronny Pries

For skiing try rubbing a piece of 8.5×11 paper or whatever in circles on a desk.
– Vince Jaeger

Sand is good for snow, if you put on a ski glove and move your hand across the sand it can sound like skiing. You can apply weight and change direction suddenly to get the effect of turning on skis or a snowboard. This works much better with gloves moving on snow, but if there is no snow sand is ok. Both are much easier and safer than trying to ski with a microphone :)
– Stephan Schütze

Use a combination of flour and corn starch and take a block of wood (like about 8 inches of a white pine 1″x4″) and rub it around according to picture. You can do all moves this way including starts and stops and everything in between. Varying the mixture can make the snow sound more or less crunchy.
– Kini Kay

Simulate glides by recording foamed polystyrene scraped on concrete block.
– Adam Skorupa