Stretching, particularly if you have a special goal, can be a physical challenge, but it is entirely possible to achieve ambitious stretching and flexibility goals. If you are determined to do the splits as quickly as possible, then you will have to place yourself in a mental state of extreme focus on your goal, particularly while stretching. You will have to dedicate a lot of time, but the splits can be entirely worth it. A yoga mat can be helpful for comfort, but is not necessary.
Stretch daily for 15 minutes in the morning and 15 minutes in the evening, or at least 2 hours apart. Include any and all leg and hip stretches, including forward leg stretches, vee sitting, toe touches, lunges, the butterfly and frog sitting. Essentially, any leg stretches you can think of will help with the splits.
Hold each stretch, including the splits (as far as you can go) for a minute each, or more if you feel comfortable. Stretch until you reach a point of challenge without feeling pain.
Add a 15-minute session to each day after 1 week, so that you are stretching your legs and practicing the splits for three 15-minute sessions each day. Hold each stretch for at least 1 minute before moving on.
Add a fourth 15-minute session after the second week. You should now be doing four 15-minute sessions (each at least 2 hours apart) every single day. Hold each stretch, including your splits, for a minute. By the end of this third week, you should be able to do the splits.