This pattern is easy and fast (took me 5-6 hours for the knitting itself, without the border).
It has an easy colored-in chart, and easy way to estimate how much yarn you’ll need.

The directions are for Baby and stroller blanket, but the chart will work nicely for:

Lap quilt / lapghan.
Full size afghan.
Tapestry / wall hanging.
Fun pillow.
Nautical bag.
Blanky.

All you need to do is change the size. This is easily done by changing yarn and needles, or by adding extra stitches on the edges.

Skills needed : reading colored chart, intarsia, and crochet for the border (or do a border of your choice).

Yarn & Needles :
The chart can be knitted with any yarn and needles.
For a thick big blanket use thick yarn and big needles.
For a smallish thing, like a stroller blanket, use thin yarn and thin needles.
This project provides a good opportunity to use up your yarn stash.

Example for Baby Blankets:
Finished Size: approx. 32”x32”
yarn: soft thick yarn (like Lion brand homespun).
Needles #15 US/9 mm
Crochet hook size K (or what you need to knit the border you choose).
Gauge: 9 sts x 12 rows per 4”/10 cm in Stockinet stitch.

Stroller blankets:
Finished Size: 16” x 19” (40 x46 cm).
With the border: 20” x 23” ( 50 x 56 cm).
Yarns - use thin soft yarn, like Carron simply soft.
Needles #7 US / 4.5 mm
Crochet hook size F for the border.
Gauge: 15 sts x 19 rows per 4”/10 cm in Stockinet st.