@pansy81 when using oils its VERY IMPORTANT to understand that youre working with layers. on the bottom layer, you should always use the most paint thinner/mineral spirits to thin the paint out, and as you add more layers use less of it
this makes the thinnest layers on the bottom and the thickest layers on the top. that way the bottom layers dry before the top layers do, preventing the surface from cracking after drying
also, you can use willow charcoal to sketch before painting. its not necessary but it can help save some paint. willow will easily wipe off with a towel, and the paint goes right over it. just make sure it isnt TOO dark before painting because it might mix together and make a gross muddy color.
another tip is, just like any other drawing from life, start with one color to mark out the darkest parts of the image first. getting the value down before adding the colors and details is important. it also allows a balanced color palette throughout the painting.
also NEVER PAINT WITH STRAIGHT UP BLACK. your darkest values should never be pure black. you can mix a *little* black with colors like brown or blue or red, but straight up black is almost never going to look right. unless you figured out a way to make it look good which hey, more power to ya.
and you dont really need to blend things in to have a perfectly opaque painting. oils are meant to have texture; being able to see the brushtrokes is what make oil paintings unique!
lastly, just watch speedpaint videos and pay attention to other peoples techniques. that always helps. but dont forget to develop your own style. nobody paints the exact same way! embrace your individuality.
anyway thats pretty much all i can think of at the moment. hopefully this helps! 🌻