How can I avoid the problem of insufficient memory when converting a sparse matrix to a dense one？

[DINGQIA]

I have over 100 samples and 1 million cells, but during the operation process, always have the following situations：
Warning message: In asMethod(object) : sparse->dense coercion: allocating vector of size 285.4 GiB
How can I avoid the problem of insufficient memory when converting a sparse matrix to a dense one？