BINGO!!
I adore this for so many reasons. First, it's Canada.
Second, three months of summer. Even in Canada. Yup, it's true, folks. We really do live in a four season climate!!
And I can just tell this insight is going to lead to genuine improvements in your wardrobe and make is so much more fun to get dressed.
(Oh -- another point -- don't forget that every month in summer has an extra holiday. So even more days for casual dressing!!)
We had an Ottawa member a few years back; I don't think she is posting any more but she was a school principal who basically had made the same realization as you; she needed a casual wardrobe and she actually didn't have one. She very deliberately went shopping. It was hard -- she didn't always like casual wear or gravitate to it. But within a few weeks to months, she had developed a fantastic casual capsule.
I think her screen name was Kristen if you want to look her up.
Anyway...I would make a list of the activities you actually do in summers both on weekends and holidays.
Note any times when you felt frustrated about not having the right clothes.
Note what others wear in these situations. You might or might not like it -- you don't have to dress identically -- but here is where your tolerance for ignoring environmental norms comes in. You do need to consider how comfortable you are with appearing "different."
From there it will be a process. You'll figure out that some types of item work really well, others not so well both for your internal style preferences and your environment.
I work from home and live in a casual city. So my "work wear" is what you might call weekend wear!
I am comfortable looking a little bit dressier than some in my environment, but I am not comfortable wearing clothes that don't allow me to do the things I want to do. I am an active person who enjoys freedom of movement. Here are my personal summer staples. Your own mileage may vary:
Shorts: I own several styles and lengths from slim Bermudas or clams to loose linen shorts to BF shorts. Some are uber-casual and some are more smart-casual. I really like white shorts -- they feel cool and a bit dressier than denim, for example. Black could also work the same way, or grey.
Woven tops: In winter, I love cozy knits for casual at home wear. In summer, it's woven tops all the way, mostly sleeveless. I really like silk, and cotton. I have a couple of linen-cotton blend button front shirts, too.
Knit tops: I also have some linen and cotton print tees that are a bit out of the ordinary. A cotton Mariner style sweater with 3/4 sleeves is great for cooler days.
Jeans: I almost never wear in summer. (I don't have air con and live where it can get humid.) But I do like to have one lightweight pair for evenings, etc. BF jeans can also work as they are looser and look good with high vamp cage sandals.
Dresses: A couple of casual summer dresses are a godsend if you wear dresses and live where it gets really hot and humid.
Footwear: Yup, those low heel, wedge, or flat summer sandals are necessary! If you do any amount of walking, that is. (If you are into hiking you probably need some gear shoes, too.) I am hard on shoes especially in summer, so I might not be representative. but I go through one to two pairs of sandals every summer. In Canada.
Denim jacket.
I also really love to have knit tube skirts and a couple of "nicer" tops for dressier situations. I love my sarong shorts (sort of like culottes). These feel more dressed up but still casual enough.
I also like cuff bracelets and belts. As well as earrings. Necklaces feel hot in summer and fussy, but cuffs are easy to wear.
