I always recommend a 10metre training line. You can hold the end and let the rest drag and the pup feels like it is off lead, rather than with a flexi-lead where they are always pulling. Then you can see how pup behaves and how she reacts to your recall. You will probably find that she stays close to you. Once you are more confident then let go of the end and if you do need to catch her, it's easy to grab or tread on the line rather than chasing a wriggly puppy. I had Dylan off-lead within a week by doing this.