During the season it depends on the recruit. If it is early in the season I will schedule earlier as the recruit seems to be moving along more quickly looking for a team and if it is later in the season I will more likely wait till the end.
If I am the only one chasing a kid I will get him in right away hoping to get him signed and be able to move the few minutes I am using on him to someone else.
If I am leading a race for a player I will typically try to be one of the last teams to have him visit. It seems that usually if you are in the lead they will only soft commit to other teams on visits giving you the chance to have your visit and move back to the front. Also, if you then get past the other team's visits without them passing you up then you can back off on the kid and get him with very little effort.
If I am back in 4th or 5th quite a ways behind I will schedule for the 1st big game I have hoping that a great visit will move me up to the front and give me a fighting chance.
If I am in a real fight for a recruit then I kinda go back and forth. Sometimes I will try to get him to the 1st big game on schedule and sometimes I will wait till the end but I usually go with the 1st big game, especially if I have boise state coming up.
Offseason, although in this game I haven't gotten to it yet, in previous games you could get a lot of commits with a good visit so I would schedule them right away.