When entering traffic, you should activate your turn signal after

100 feet (in terms of distance)

Explanation:

First you look around to check the flow of traffic around you on the rear, sides and front.

You then look for a little gap of 4 to 5 seconds in traffic before activating your turn signal. 

You do all these at a distance of at least 100 feet before you make the lane change).

Check your mirrors (rear-view then your side mirrors).

it is not paas i hope that