When starting out, it's very important to learn proper form for squats. Begin squatting using only your body weight, allowing your muscles and joints to become accustomed to the movement. This also allows you to work only on your form until you have it perfect. Standard squats should be performed with your feet shoulder-width apart, your head up and shoulders back. When lowering down into the squat, push your glutes back and keep your weight nearly all in your heels. Your knees should never extend out farther than your toes. Begin your routine with three sets of 15 repetitions. google it to see the routine.
Next lunges you should perform it using only your body weight as resistance until your form is perfect to be safe. When lunging, have most of your weight in the heel of your front foot and never allow your knee to extend out beyond your toes. Push through your front heel and squeeze your glutes to rise up from the lunge. Backward lunges are often easier to perfect if you're a beginner. All forms of lunging help with balance while toning and strengthening your legs and glutes. Start with three sets of 15 repetitions per leg. Again google it for pictures.
For The leg extension and leg curl. Use resistance bands google that also.
When you perfect the basic form of squats and lunges, you can then add these plyometrics. It's the quick and complete contraction of the muscles needed to perform these exercises leads to strong and toned legs. Begin the exercises in the standard squat or lunge form and push through your heels to hop off the ground with as much power as possible. Bend your knees upon landing to cushion your joints from the impact and return back to the starting position. Perform two sets of 10 of each with no weight.
Stretching helps to eliminate post workout soreness and tightness that can lead to injury during other activities. It also helps to get leaner and longer leg muscles that will give you the look you desire. End your leg resistance training with 10 minutes of stretches for the legs, glutes and lower back.
Before doing anything get the OK from your doctor.
Toning them will be the only way to just target your thigs. Leg and butt workouts will help. And honeslty, unless you're overwight, you might just be built that way. Which is not a bad thing! Naturally thick thighs can be very atractive and can be awesome for biking and running!