Rounded Ti Bolts

Tricky one here… rounded a Ti allen key bolt (located on my cranks – hollowtech 2 Ultegras).

Any top tips fpr removing it before I either :
a)make a complete obllox of it and end up having to grind my cranks off and buy a new non-drive side crank,
or
b) lose lots of blood/layers of skin, swear repeatedly then have to take it to the bike shop

Answers on a postcard, please and thankyou in anticipation