All depends where you hunt and then with who.
Baiting(distance from bait will be determined by terrain etc.) 50-100 meters.
Tracking, again determined by where. If fresh tracks are found and the terrain allows(sandy), they can be followed, especially when picked up early morning as the cats will rest up as soon as it heats up.
Opportunistic, meaning hunting during the rest of the day and bumping into lions while doing so, you should not look the gifted horse in the mouth(purely luck when this happens though). Fast decision making and action required when engaged.
Calling, can be very effective and may require more than a few day's to produce. Time consuming but you can call large male lions from a long distance off, especially the dominant ones. However as mentioned not legal to do so in many countries.