pENTR™11 Dual Selection vector needs to be transformed in ccdB resistant E. coli cells. If you are using commercial competent cells (One Shot ccdB Survival T1 Phage- Resistant Cells) you can use pENTR™11 Dual Selection entry vector in ng amount for propagation but make sure to plate transformed cells on LB + Kanamycin 50ug/ml + Chloramphenicol 25 ug/ml plate.

It would be enough if you go with the pipette tip into the plasmid solution and afterwards with this tip into your competent cells. The amount of plasmid outside the tip will give you enough colonies.