In highland dance you are always on the balls of your feet, and your legs(knees) are always pointing out(to opposite sides). Therefore, those are the two major parts you want to focus on when stretching. Some stretches i can tell you about are the following:
1) Place one foot forward a little on a diagonal from your other foot. Keeping your weight on the back foot, with the foot in front, lift your heel and be on the ball of your foot, then place all of your weight onto that foot. Hold for 10 seconds then switch, bringing that foot back and placing the opposite foot in front.
2) Sit down on the floor and place the bottom of your feet together(this should make your knees turn out to the sides). Hold onto your feet then slowly and carefully press your elbows down on your knees so you push your knees down closer to the floor. Hold for 10 seconds then let go and do it again about 5-8 times.
Tips- If you are not feeling the stretch in #2 then bring your feet in closer to your body.
There are many stretches you could do but these are the most basic ones you can do. You may also want to stretch your arms before dancing to; it is not necessary but it does help.
In Jazz again you will mostly be on the balls of your feet unless you are preparing for a jump, or spin (pirouette, fouette turn) but all through dance, you are going to use just about every single muscle in your body so you have to stretch well.
1) Stand with your feet shoulder width apart, shoulders back and arms in second position (parallel to the floor). this is where your going to start to stretch to from the top to bottom. roll your neck from one shoulder to the other, count to 8 as you do this, you should be at 4 every time your ear gets to your shoulder. Do 8 counts and 4 reps.
2) spread you feet out a little further and and reach your hands down to the floor. Hold to the middle between your feet, for 8 counts switch are reach towards your right foot, and hold for 8 counts repeat for the left side. After wards still reaching down as far as possible, walk your feet together slowly so your reaching to your toes.
3) Sit on the floor with your feet out and together, straight in front of your body. try to keep your back straight and shoulders back, point your toes and reach your hands towards them and hold for 8 counts. repeat this step 4 times rotating between pointing and flexing your feet. Afterwards take your left hand and grab the heal of your left ankle or heal (depends how far you can reach and keeping to the outside of your leg) and bring it up to shoulder hight, wile turning you body to the right and brining your arms into second. Repeat for other side.
-Always were your good condition jazz shoes, or bare feet or you could slip and hurt yourself.
-Never over streach your body, because you could pull a muscle.
-Always point your feet and keep your arms and legs straight, unless your doing moves with "Audited".
-Never start dancing before stretching or you can really hurt yourself (even the professionals know this)
-Always have fun :)