Some of the little toys that hang from the handle of infant seats are better than others. Using soft toys that you wouldn't mind throwing at your child's head are not as worrisome as the hard plastic toys. These toys are fine to use outside of the car. Just remember that these toys can become projectiles in a crash, as with any loose item in your car.
Wether to use a mirror or not can sometimes be a tough choice for parents. I understand this, as a parent I had to make this tough choice. My youngest had reflux and was constantly spitting up. I was worried she would choke while I was driving. I made the parental choice to find a mirror I felt was secure and soft. I used it until she stopped spitting up. Many parents have to make this choice and its not easy. When faced with this choice make the best one you can. Use a mirror if you need to but try to find a soft flexible mirror that fastens to your vehicle as securely as possible. If you dont need it dont use it. Most children are fine without one.
Window ShadesIf the harness strap covers do not come with your car seat do not use them. Most of the after market harness covers push the chest clip down on to the belly which is dangerous. They are also not tested with your car seat. They can interfere with the tightness of the harness. Even though it feels tight these harness covers could compress during a crash. Luckily many car seats provide their own crash tested harness cover straps with their seats. If this is an important feature for you then make sure you select a seat with harness cover straps.
Again another possible projectile. Avoid the kind with hard plastic parts. There are some that just cling to the window without any hard plastic parts. Like this product. These are a safer option to window shades.
Harness Strap Covers
If your child's car seat doesn't come with a head support do not use an after market head support that interferes with the harness or goes behind the child's back. These can compress during a crash and give a false sense of tight harness straps.
So what do you do if you have a newborn with a floppy head and no head support? You can first check the recline on your infant seat. The infant seat should be at a 45 degree angle for newborns. If this still doesn't resolve the issue then you may use rolled receiving blankets around the babies head.
There are safe and non safe bunting bags. You never want to use a bunting bag that goes behind the child's back and interferes with the harness. It can compress in a crash and give a false tightness of the harness. But one that fits like a shower cap over the seat is a safer option.
There are companies that make covers for car seats. Although these are very cute they are not safe. They have not been crash tested with the car seat, they can compress during a crash, they can interfere with the harness, they do not have important warning labels on them, and they have not been treated with the flame retardants that are required by the federal motor vehicle safety standards.You should only purchase a cover from the manufacture of your child's car seat.
Some car seats allow for a THIN towel or blanket to be used under their car seats. You'll need to read your car seats manual to know this for sure. Thick seat protectors or seat protectors that are used on unapproved seats can be dangerous. They can compress in a wreck and give you a false tight installation.
Seat Belt Tightener
These are a BIG NO NO! Do not use one of these. You don't need to. If installing your seat correctly you will be able to achieve a tight install. Seat belt tighteners can over tighten your seat belt, break parts of your seat belt or car seat, and can possible break free in a crash and become a heavy projectile. They are not tested with your car seat and you shouldn't use them, nor do you need them. Seek help from a Child Passenger Safety Technician if you aren't getting a tight installation.
Many of these types of products are not safe and should not be used. It is likely that you don't even need them. So pass up the car seat accessory isle in the store, as tempting as it may be.