how do I improve my chances of an FET?

💞SuE💞 • 39/ TTC#1 4 rounds of clomid at 25mg. 1 round of ivf/fet failed dec16. 2nd round fresh failed 14feb17. fet in april17
slowly moving forward and making progress with getting nearer to having my FET
had the mock transfer which was ouch!!!! so next time I'm in the same position it will be the real thing
I start injections this month and I have a month and a half before the real thing.... 
so I'm wondering, what can I do to improve my chances of the FET succeeding?