alright i don't know how good I am at explaining this but here it goes.
Ok so its kinda like a squat but your in this ballet type pose where your feet are facing out and they are sholder lengh appart and then you bent your knees and go down till about a little lower then you would sit at, then repeat, but don't go back standing up till your all the way done, always have your knees bent till then end of the set.
walking on the treadmill at a high incline makes the inner thigh muscles very tight and strong. If u dont have a treadmill you could always walk up a hill or something that is high inclined.
So, inner thigh work is anything that squeezes your thighs together.
For example, you can put a soccer ball, beach ball or cushion between your knees and squeeze it.
There are standard machines for doing this, too. Most gyms have a combined 'thigh abductor/adductor' machine. 'Abduct' means 'to take away', and the abductor provides resistance while you move your legs outwards. Adduction is the 'squeezing together' movement, and the machine will allow you to do this against resistance.
You can get home-use devices as well. the most popular is like a big springy opened-out paper clip. Just like the ball, you put it between your knees and squeeze.
If you want to do something more active, skating uses the outer and inner thighs for most of the propulsion. Really good 'crossover' technique will target your inner thigh in particular.
The amount you do, rather than how hard you work, is important. So it can be useful to get into the habit of sitting very upright so that you can put your knees together, and repeatedly squeeze them against each other. In this way, you can do a lot of inner thigh exercises during normal daily activities. Unfortunately, you may find this movement too stimulating in other ways.
Pilates is well known for its effectiveness in toning the abdomen and the rest of the Waist (or 'core'), but it is also very good for the condition of your inner thighs.