The risk of SIDS (sudden infant death syndrome) is higher in babies who get too hot, according to safer sleep charity The Lullaby Trust.
The room temperature should be between 16 and 20°C and this can be checked with a dedicated room thermometer.
Typically many baby monitors also tell you the temperature of the room. Go to our baby monitor reviews to see which ones we've tested.
Make sure to keep your baby out of direct sunlight and read our guide to baby bedding safety for a full list of what sheets and blankets you need for your baby.
Bedding should be lightweight or choose a baby sleeping bag of the correct tog and size to ensure their comfort and safety, whether it's the middle of winter or the height of summer.
How to check if your baby is too hot
Feel your baby's chest or the back of their neck. If their skin is hot or sweaty, remove one or more layers of bedding or bedclothes.
Don't use your baby's hands and feet to judge temperature as these will usually be cooler than the rest of their body.
If you swaddle your baby, check their temperature to ensure they're not too hot. Use thin materials, don't swaddle above the shoulders or too tightly, and never put a swaddled baby to sleep on their front.
Although babies should be put to sleep on their back, they can roll over onto their front from four weeks old and there can be a gap of a few months before they learn to roll from front to back, making it vital that they sleep on a flat surface.
Car seats put your baby in a semi-supine position - a 45 degree recline angle which provides good support for your baby's neck and head during transport.
But this position can restrict their breathing, so try not to use a baby car seat for more than 20-30 minutes at one time in the first four weeks after their birth, and for no longer than two hours at a time from six months upwards.
This means taking regular breaks if travelling in the car on long journeys and once you're home or at your destination, you should move them to their usual firm, flat surface to sleep.
Your baby should be in a properly designed and fitted car seat. Go to our child car seat fitting guide for our free downloadable car seat fitting checklist.
The Lullaby Trust says: 'Using a cover also creates a barrier between parent and baby, which is slightly risky as parents won't be able to see if their baby is having difficulties or monitor their temperature easily.'
Instead, attach a clip-on sunshade or parasol, regularly check if your baby is getting too hot by feeling their chest or back of their neck and keep them out of direct sunlight as much as possible.
If you're carrying your baby in a carrier or sling, follow the 'TICKS' rules for safe baby-wearing, and read our guide to baby carrier safety to learn about safe positioning for your baby.