The first every beanie I made was from an excellent site called Happy Berry Crochet. The creator of this page had done a series of basic double crochet (dc) beanies from premmie to adult. Adult beanie pattern here.
Once I worked out how to crochet in the round I was in love with them. It is still my basic go-to beanie pattern when my youngest son decides he needs a new beanie (he has the biggest collection in the house). Over the years I have made a few adjustments to the pattern depending on what it will be for. What I found mostly is that because in Australia our yarn grading is different, if I am using a standard 8 ply yarn I needed to make more rows than the suggested requirement if it was for an adult. I also started to make the starting 2 chain at the beginning of each round NOT count of the first dc. This means I always add an extra dc after the 2ch into the same stitch so I can hook into the top of the stitch instead of the second look of the chain. This creates a more invisible seam which can be particularly noticeable with the lighter weight yarn (the pattern was originally designed for chunky/bulky).
And the other little addition I like to throw in every now and then is the turned up brim. This is a trick I adapted from another beanie pattern and will often do for adult beanies where the person prefers a brim.
The yarn I have used in this one, which has fast become a favourite, is Lion Brand Yarn – Heartland. I have used two colours here alternating colour every 2 rows, but have done many different combinations of stripe and plain colours and it always works out a treat!.
Here is the basic pattern using a 6mm crochet hook (use 5mm if it is 8ply):. Terminology used is US so a dc is a treble in Australian terms.
Round 1: ch 5, sl st in ch 1 to form a loop. ch 2, crochet 12 dc into loop. sl st in top of first dc.
Round 2: ch 2 (does not count as first dc). 2 dc in same stitch as chains, then 2dc in each stitch around (24) sl st into top of first dc.
Round 3: ch 2, 1dc in same stitch, 2dc in next, 1 dc / 2dc pattern around to beginning. sl st in to of first dc.
Round 4: ch 2. 1dc in same stitch, 1dc in next st, 2 dc in next st. 1dc/1dc/2dc pattern around to the beginning. sl st into first dc.
Round 5: ch 2. 1dc in same st, 1 dc in next 2 stitches, 2 dc. (1dc/1dc/1dc/2dc) pattern around to beginning. sl st into first dc.
Round 6: ch 2. 1dc in same stitch. 1dc in next 8 st. 2dc. (1dc in next 9 stitches, 2dc) around to beginning. sl st into first dc.
Round 7 – 20: ch2, 1dc in each stitch ( including beginning stitch).
When you think its long enough and you’re ready for a brim ch 1 then turn your work around. You are now going to crochet into the front loops of the stitch only.
Brim round 1: fpdc into each stitch around to beginning..
round 2 & 3: dc each stitch around to beginning..
round 4: sc each stitch around.
I have left the colour changes up to you. I do something different every time. Sometimes I will do a hdc as round 3 of the brim depending on how big I want it, and if I want to do more colour variations.