I tend to get solder started on the wire itself, by holding the wire and solder in left hand, and heat the wire from underneath and let the solder soak into the end of the wire. It seems to make it easier for getting the wire onto the contact point. After the wire is on the contact, I'll try to smooth over the solder, and add more as necessary.

Depending on the age some solder takes significantly more contact time with iron to get mold-able, so the addition of new solder to the wire seems to help that as well.

If the contact doesn't already have solder, as in a new contact, I'll put solder on that end as well.

I'm far from a pro, but that's what has helped me.