I have seen workers in pet stores catch birds with a net.
Hand or net, the budgie is going to fly around to avoid being caught.
I also agree with Aluz that getting to know your lovely flock would be a great idea before adding anyone else.
Every time you get a new bird, you add a new unknown element to the flock and you won't know how they will get along with the others until you get to know their personalities.
All the birds I have added to my flock this year, have been carefully selected by observing them for a while in the pet store to see how they interacted with others. Only then would I make a decision on who to bring into the flock to keep harmony within.
Remember that if you have a situation where your birds don't get along, you will have to split them up for their own well being.