For ICs: Just flux pen a little, then put some solder on one pin in the corner. Then put the chip near it. Now just flow the solder with your iron and nudge it into place with a pick, tweezers or the finger whatever works for that part. Then you can align all the other sides by heating the solder a little and nudging it. Then tack the opposite corner and off you go.
For little parts: put a bit of solder on one pad then heat it up and slide one pad of the component in with the tweezers. Pull the iron off and it stays in place, you can use as much force on the tweezers as you need to. Then just finish up the other pins. You can go pretty fast with this if you’re placing multiple parts just prepare one pad on each footprint, then slide in the parts and then go back and do the other pins.
Read More: SMT PCB Assembly