What tips do you provide patients on therapeutic LMWH who have difficulty with injections and are bothered by bruising?

I counsel patients that injection site bruising is extremely common and should be expected. To try to limit the impact, they should make sure they are avoiding injection into the superficial blood vessels on either side of the abdomen. Sometimes moving to thighs or upper arms can help. If injections are painful, icing the area prior to injection or trying a counter stimulus (several devices are available for use in toddlers prior to vaccinations) device. Fondaparinux, in my experience, has less pain with injection and has the advantage of once daily dosing. A Cochrane meta-analysis showed there might be a decrease in bruising with slower injection speeds.

Mohammady et al., PMID 34101161

I am privileged to have a team of clinical nurse coordinators who have a lot of experience with thrombosis and hemostasis, so I often turn to them for their wisdom and have them actually meet with patients in-person at times to help troubleshoot technique. One of the biggest concerns I hear is that the bruising is so much across a patient's abdomen that they "don't have any other places to inject". In those cases, I advise them to try injecting in the upper outer thigh, as they have enough subcutaneous tissue, and in many cases that is able to resolve the issue.