Open tailed ring sling
Description: There are two types of 'ring sling'. The first is called an 'open tail' ring sling (see picture), like the Keoni, Starflower and Zolowear brands. They are a length of fabric with two rings at one end. The 'free' end (called the tail) threads through the rings to create a 'pouch' which supports baby. The ring sling shoulder part may be sewn in a variety of ways (SBP pleated / hot dog/ gathered/ accordion/ etc) to encourage the fabric to spread across your back. Because both types of ring slings are adjustable, one sling may be used for both parents which makes them cost-effective. Ring slings are made of a variety of fabrics: cotton, silk, and solarveil are a few.
The second type of ring sling is a 'closed tail' sling like the Nature's Sway, Dr Sear's 'Original Baby Sling', and Baba. They usually have padded rails and it may have a clip instead of rings. Many people find them less intimidating than slings with a lot of fabric on the end. They are worn in almost the same way as normal 'open tail' ring slings, but without adjusting each rail for fitting, and usually only facilitate a cradle and hip carry. The padded rails are good for cushioning the back of baby's legs in a hip carry.
Learning curve: Medium
Open tail slings:Make sure the fabric is threaded through straight, no twisting. The sling should rest on one shoulder, leaving your 'dominant' hand free. The rings need to be 'too high' to begin with, then as you pull the tail to adjust and tighten the sling, the rings will come down to about 'corsage' level. The fabric should be away from your neck, close to the edge of your shoulder or even slightly capping it if the shoulder design allows. Baby should be worn snug and high, their position mimicking how you would carry them without a carrier. Knees up, bottom down. Each rail (edge) can be tightened individually, the bottom one to lift baby up, and the top rail to bring baby closer to you.
Closed tail slings: the clip or rings should be in corsage position as with any ring sling. Wear the shoulder strap more towards the edge of your shoulder, away from your neck. The wider the shoulder strap, the more it will spread the weight. Baby should be in the sling either diagonally for the cradle position, with their head touching the outside rail and bottom more towards you; or sitting up in the hip carry once they are able to sit up themselves. Pull up any extra rail/fabric on the inside, and tuck it in the sling. The strap will feel better on your back if it is low and spread as much as possible.
Positions: 'Open tail' ring slings are worn using the same positions as pouches, with the added bonus of adjustability for a really nice tummy to tummy carry. Cradle, upright cradle, tummy to tummy, kangaroo, hip, back. 'Closed tail' ring slings usually do a nursing/cradle carry and a hip carry.
Pros: Adjustable, low learning curve, versatile, open tail is good to cover up in the sun or to breastfeed.
Cons: One shoulder may tire after a while with a heavy child. Closed tail ring slings can be difficult to get a snug fit.