Worth remembering, white signal lights in marine terms, a solid white light that shines 360 degree's is the boat at anchor signal/Stern Light. A white flashing light, as in a strobe light, is to signal "man overboard" and that is why some PLB's and EPERBS are fitted with strobes.
Also worth noting;
International Collision Regulations > Part D - Sound And Light Signals >
Rule 36 - Signals to attract attention
If necessary to attract the attention of another vessel any vessel may make light or sound signals that cannot be mistaken for any signal authorized elsewhere in these Rules, or may direct the beam of her searchlight in the direction of the danger, in such a way as not to embarrass any vessel. Any light to attract the attention of another vessel shall be such that it cannot be mistaken for any aid to navigation. For the purpose of this Rule the use of high intensity intermittent or revolving lights, such as strobe lights, shall be avoided.
While the regulations for kayaks here in Victoria do not require a fixed white light or port/starboard side lights, if you wish to attempt to do it right under Internationally recognised lights, this may give you some advice;
OTEN Maritime Studies - Maritime Training for GPH, Coxswain, Master, Deck Watch keeper and Marine Engine Driver (MED) qualifications - Part C - Lights and shapes But remember, a recreational boat/kayak etc, trolling fishing lines, and being used for fishing, is not a fishing vessel.
