Yes, you can do it, 26 is not too old. I know people in their 40's who got their splits for the first time.
Here are some things that can help. Definitely get really warm before you practice, it will help. Do some cardio, it will make your stretching more effective. It's also key to make sure that you hold the stretches long enough for your muscles to actually stretch. This means at least 2 minutes--this is how long it takes for muscle fibers to actually stretch. Go down into the splits as far as you can and hold for at least 2 minutes (great to do when watching TV). Do this everyday. This is what they had us do in gymnastics class, our warm up consisted of going into the splits and holding for usually 3 minutes. They would periodically test us to make sure we could always do them.
You can also do runners lunges to stretch out your hip-flexors, and half-splits to stretch your hamstrings. I also found this page, which has some additional stretches for your back and gluts among other things:
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