Hi Louise
I felt just the same way when I started out on the Scottish line.
I thought someone might have responded by now, so I'll have a go.
I did learn to do a lot of checking where I could on Family Search and what I knew from the family beforehand, though obviously Family Search doesn't have the same collection necessarily.
Put in a broad search first (eg no parents, no parish, county only) and add in extra search terms, narrowing it (eg birth years) to see the effect on the number of results and pages. Try to narrow possible down to one or two pages of index results. Don't view the image unless you are sure, obviously (or curious)
Think a lot about the surname and forename options (what kind of matching do you want? I don't understand all the options but some give you many more matches).
Change one thing at a time to see the effect on the number of matches.
It took me a while to realise that all my previous images and pages of results are saved in Scotland's People against my account so they're free to look at again, in case you find yourself accidentally repeating the same search! Easily done in desperation.
I just tried it again with my GG grandfather Robert Allan, such a common name. Though I still haven't found his 1818 baptism.)
Hope this helps
Good luck
Jenni