I suggest you compare with her what you would have done to complete the task with what she did, step by step, just this time and a few times in the future for different types of tasks.

I would make it clear how puzzling it is that she took so much longer and that you want to bring her to the level that is needed to be a respected co-worker.

Similarily, reflect to her how inappropriate it is to imply being bored and surfing the web during working hours. On the other hand, being honest and open is valueable, so I suggest to show her outlets like surfing in working breaks, being bored after she completed the task or finding out why she is bored while she has a task.

After a few days I hope you'll get a feeling for whether she integrates your advice into her habits. Because if she does not, she is wasting your time.

I suggest you go through with her and compare what you would have done to complete the task with what she did, step by step, just this time and a few times in the future for different types of tasks.

I would make it clear how puzzling it is that she took so much longer and that you want to bring her to the level that is needed to be a respected co-worker.

Similarly, reflect to her how inappropriate it is to imply being bored and surfing the web during working hours. On the other hand, being honest and open is valuable, so I suggest to show her outlets like surfing in working breaks, being bored after she completed the task or finding out why she is bored while she has a task.

After a few days I hope you'll get a feeling for whether she integrates your advice into her habits. Because if she does not, she is wasting your time.