If you mean "how can I claim the tuition payments" as a deduction on your return then the answer is you cannot.
The student (or whoever claims the student on their return) will be able to claim the education credit using those amounts that you paid on their behalf (since it is technically a gift to the student).
If you paid the school directly then the amount paid is not relevant however if you gave the student more than $14K in one tax year then you may need to file a gift tax return. See the rules here: https://www.irs.gov/Businesses/Small-Businesses-&-Self-Employed/Filing-Estate-and-Gift-Tax-Returns
