SAS
The current procedure for 'zero vis' (for want of a better term), is from an IGE hover note Torque, heading and attitude (usually about 5degs nose up and 3degs Right skid low in the AS350 I fly).
Take off is initiated by applying 10% more torque, retain attitude and heading until Rate of Climb indicated on VSI/Altimeter then select 10 degs nose down (from hover attitude). Retain right skid low until 40kts then select wings level whilst continuing accel, in balance (in trim in US), to climb speed and topping up torque. Establish on normal climb parameters.
If cloudbase permits, a VFR transition to climb speed followed by reverting to instruments in the climb is the preferred option however.
JJ