The technique of filler injection would depend on the type of filler and the depth within the skin or under the skin.
Safety precautions include
1: use of local anesthetic with epinephrine to make blood vessels vey small.
2: Use cannula instead of needle to inject the filler
3: inject as the cannula is drawn back
This will minimize the risk of intra-vascular injection, more control of the injection technique
Do not micromanage your doctor
There are many techniques for injecting soft tissue fillers. This is part of the "art of medicine". What works well for some physicians may not work well for others. I recommending finding a doctor who is highly experienced, has a good reputation, who listens to you and understands your concerns and who you trust and let them do their job in the manner that allows them to produce best results.
There are several different techniques for injecting fillers such as Juvederm. Experienced injectors can vary their technique depending on the patient, site of injections and the product. It is important to choose an experienced injector with whom you are comfortable and rely on his /her judgment.
Juvederm injection techniques vary
there are many different ways to inject Juvederm, Restylane, Restylane Silk and Belotero. Although dermatologists do more non-surgical cosmetic procedures than any other specialty, make sure your doctor has a lot of experience with dermal fillers as not every dermatologist does a lot of this.
Injection techniques for Juvederm
Injection technique depends on the location, wrinkles/lines, and skill of the physician. Often we use different techniques for different things. There is what's called "fanning" which means the syringe is inserted and kind of wiggled in there like a fan while injecting, there's also bolus technique where small boluses of material are inserted, and then there's what you are talking about where the needle is inserted and the filler is injected as the needle is pulled out of the skin. This is what's often used for finer lines and wrinkles because it goes in smoother and finer.
"This answer has been solicited without seeing this patient and
cannot be held as true medical advice, but only opinion. Seek in-person
treatment with a trained medical professional for appropriate care."