Don’t wait until then. I admit I can’t understand half of things written there, probably because they’re written and not spoken, but Google Translate is fair good helping tool so I’m just pushing on.
My strategy of Clecs-ing: I try to read a “clec” then I try to (quickly) establish what I understood out from written,. Then I copy the “clec” and put it into the Google Translate to establish if I really understood it correctly. Most of the time I matched at least the context of it. When replying I write the reply into Google Translate Welsh to English way what means I write it in Welsh and see the translation of it. If I want to use the word I don’t know I either check into dictionarry or go for translation with Google Translate but I NEVER copy/paste this new word into my sentence but rather manually type it into it so I can memorize it in time. The same goes with the whole sentences. Even if it doesn’t go Welsh-English way but rather oposite way I first check if there can something I already know be used and when sentence is ready to write it down I type it manually into the clecs box so I create a possibility of remembering it in a time. You can of course save your favourite translations into Google Translate if you have Google acount and use them later but even that way I’d type them manually to ensure I would be able to type/write things in Welsh without that one day.
Might seam complicated and takes a bit of time but it’s rewarding at the end. So, join us before you think you’re really ready. You know this “when I’ll be ready” is also part of our (yours and mine) common problem of being perfectionist. 
Let’s get rid of this silly problem! SSi way praises mistakes so should FINALLY we, too!
(Gee, who would tell, my inspiration goes high today.)