I could go on for hours about this topic! I’ve recently fallen down the ancestor veneration rabbit hole, so I figured I’d pass my suggestions along to you as well 
There are lots of great resources on Spells 8 – two of my favorites are this article on creating an ancestor altar and this one on ancestor candles.
There are also some great discussions here in the forum that have lots of good resources mentioned in them, and I like to reread them when I’m looking for inspiration for my ancestor work. This discussion contains lots of great information about beginning to work with ancestors. There was also this Weekly Challenge on ancestor work.
I also just finished reading a book on ancestor veneration that I am working on posting a review about and will update this post to include it as soon as I get that review posted. Update: Here is my review of Ancestral Whispers: A Guide to Building Ancestral Veneration Practices by Ben Stimpson
@starborn’s post above regarding meditation is an AMAZING place to start also! I’m bookmarking that post so I can circle back to it and use it myself! Thank you for sharing that post, starborn! It’s fantastic, and as someone who has a hard time with visualization, I really loved the “allow your words to meld with the surrounding energy” – I’ll have to use that! 
Another suggestion I’d like to throw out there is not to try too hard to connect. In my experience (others might disagree with me, though), when I try to force anything by trying to reach out to my ancestors and spirit guides, it prevents anything from happening. Whenever I’ve had the most moving experiences with my ancestors, it’s always been when I wasn’t trying. Remember to relax and go with the flow – that’s what helps me the most with everything – spiritually and mundane!