Tricky one, a lot will depend where you live and what jobs are available there or if you are willing to move. It sounds like you are young and recently graduated though which will partly play in your favour in that you will be able to go for relatively junior roles rather than trying to muscle in further up the ladder.
I’d be searching out and scanning all the renewables jobs sources/email lists/recruiters, get active on linkedin, identifying all relevant companies and getting a cv and covering letter to a named person. I guess these days there’s lots of kids leaving uni with degrees in renewables etc so probably a lot of competition so make what work experience you do have stand out, eg budget/time/project/client management, team working, initiative, etc, etc. I’ve never had a job that’s been advertised, always word of mouth through friends in the industry/passing CV around.
My own experience is ten years of consultancy in on/offshore wind, O&G, wave and tidal and HVDC interconnectors. I’ve noticed a drop in the number of vacancies available in the last few years and a lot more competition, failure of governments to cohesively support the industry has led to the wave of optimism there was ten years ago fading a bit though there are big projects still going ahead. I’m not sure what the smaller end of the renewables industry is like, I imagine solar/small turbines are still ticking over.
I’m also trying to get back into the industry and might have to move, currently pursuing an opportunity in that London…
Oh and if you fancy moving overseas, I would be keeping an eye on overseas renewables if we continue to drop the ball here in the UK – French tidal/offshore wind, Indonesia tidal, even the USA. Keep an eye on http://renews.biz/ to get an idea of what is happening where.