My least favorite method of rolling ability scores has always been "roll for stats, then assign" - it combines the unfairness of rolling with the lack of surprise from point buy. This method reverses that precisely. Ability scores always add up to 63, but taken individually each has the same distribution as a regular 3d6 roll, and which abilities are best and worst are, of course, random.

If you're playing a later edition of D&D/decendants thereof where 4d6 is more normative, the following isn't as fair, but still gets at the spirit of the thing.

In addition to clicking once and "rolling" (so to speak) with it, you may wish to click as many times as you like until you get the stats you really want (Con of 10+ and Int of 14+ for a wizard, say) and letting all the rest inspire how you flesh out the rest of this character. Or whatever!